The 2015 Pacific hurricane season is the second-most active
Pacific hurricane season
A Pacific hurricane is a mature tropical cyclone that develops within the northeastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regio ...
on record, with 26 named storms, only behind the
1992
File:1992 Events Collage V1.png, From left, clockwise: 1992 Los Angeles riots, Riots break out across Los Angeles, California after the Police brutality, police beating of Rodney King; El Al Flight 1862 crashes into a residential apartment buildi ...
season. A record-tying 16 of those storms became hurricanes, and a record 11 storms further intensified into major hurricanes throughout the season. The Central Pacific, the portion of the Northeast Pacific Ocean between the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
and the
140th meridian west
The meridian 140° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The line is the divider in the area of ...
, had its most active year on record, with 16 tropical cyclones forming in or entering the basin. Moreover, the season was the third-most active season in terms of
accumulated cyclone energy
Accumulated cyclone energy (ACE) is a metric used by various agencies to express the energy released by a tropical cyclone during its lifetime. It is calculating by summing the square of a tropical cyclone's maximum sustained winds, measured ever ...
, amassing a total of 287 units. The season officially started on May 15 in the Eastern Pacific and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the
Northeast Pacific basin. However, the formation of tropical cyclones is possible at any time of the year. This was shown when a tropical depression formed on December 31. The above-average activity during the season was attributed in part to the very strong
2014–16 El Niño event.
The season featured several long-tracking and powerful storms, although land impacts were often minimal. In June,
Hurricane Blanca The name Blanca has been used for eleven tropical cyclones in the Eastern Pacific Ocean.
* Hurricane Blanca (1966), never affected land, travelled 4,300 miles during its lifetime.
* Tropical Storm Blanca (1970), did not make landfall.
* Tropical St ...
, an early season Category 4 hurricane, killed four people due to rough seas.
Hurricane Carlos caused minor damage while passing a short distance off the coast of Mexico. In July, the remnants of
Hurricane Dolores brought record rainfall to
Southern California
Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...
, killing one and causing losses worth over $50 million. On August 29, three Category 4 hurricanes (Kilo, Ignacio, Jimena) were all active simultaneously in the Pacific east of the International Date Line for the first time in recorded history. In September, moisture from
Hurricane Linda contributed to storms that killed 21 people in
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
. Later that month,
Hurricane Marty inflicted $30 million in damage to the southwestern coast of Mexico. In October,
Hurricane Patricia
Hurricane Patricia was the strongest tropical cyclone on record worldwide in terms of wind speed and the second-most intense on record worldwide in terms of pressure, behind Typhoon Tip in 1979, with a minimum atmospheric pressure of 872 mbar ( ...
became the most intense hurricane ever recorded in the Western Hemisphere, with a
central pressure
Atmospheric pressure, also known as barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1013.25 millibars, 7 ...
of 872
mbar
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea leve ...
(
hPa HPA may refer to:
Organizations
* Harry Potter Alliance, a charity
* Halifax Port Authority, Canada
* Hamburg Port Authority, Germany
* Hawaii Preparatory Academy, a school in Hawaii, US
* Health Protection Agency, UK
* Heerespersonalamt, the Ger ...
; 25.75
inHg
Inch of mercury (inHg and ″Hg) is a non- SI unit of measurement for pressure. It is used for barometric pressure in weather reports, refrigeration and aviation in the United States.
It is the pressure exerted by a column of mercury in heigh ...
) and 1-minute
sustained winds of 215
mph (345
km/h
The kilometre per hour ( SI symbol: km/h; non-standard abbreviations: kph, km/hr) is a unit of speed, expressing the number of kilometres travelled in one hour.
History
Although the metre was formally defined in 1799, the term "kilometres per ho ...
). After also becoming the strongest landfalling
Pacific hurricane
A Pacific hurricane is a mature tropical cyclone that develops within the northeastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regio ...
on record, Patricia claimed 13 lives and was responsible for $463 million in damage. The season's activity continued into November when
Hurricane Sandra became the strongest Pacific hurricane ever recorded in that month. Damage across the basin reached $566 million (2015
USD
The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official ...
), while 45 people were killed by the various storms.
Seasonal forecasts
On April 10, 2015, the
Servicio Meteorológico Nacional (SMN) issued its first outlook for the Pacific hurricane season, forecasting 19 named storms, 11 hurricanes, and 4 major hurricanes. The organization listed a set of seasons with similar atmospheric and oceanic conditions, including
1982
Events January
* January 1 – In Malaysia and Singapore, clocks are adjusted to the same time zone, UTC+8 (GMT+8.00).
* January 13 – Air Florida Flight 90 crashes shortly after takeoff into the 14th Street bridges, 14th Street Bridge in ...
,
1986
The year 1986 was designated as the International Year of Peace by the United Nations.
Events January
* January 1
** Aruba gains increased autonomy from the Netherlands by separating from the Netherlands Antilles.
**Spain and Portugal ente ...
,
1991
File:1991 Events Collage.png, From left, clockwise: Boris Yeltsin, elected as Russia's first president, waves the new flag of Russia after the 1991 Soviet coup d'état attempt, orchestrated by Soviet hardliners; Mount Pinatubo erupts in the Phil ...
,
1994
File:1994 Events Collage.png, From left, clockwise: The 1994 Winter Olympics are held in Lillehammer, Norway; The Kaiser Permanente building after the 1994 Northridge earthquake; A model of the MS Estonia, which Sinking of the MS Estonia, sank in ...
,
2002
File:2002 Events Collage.png, From left, clockwise: The 2002 Winter Olympics are held in Salt Lake City; Queen Elizabeth The Queen Mother and her daughter Princess Margaret, Countess of Snowdon die; East Timor gains East Timor independence, indepe ...
, and
2014
File:2014 Events Collage.png, From top left, clockwise: Stocking up supplies and personal protective equipment (PPE) for the Western African Ebola virus epidemic; Citizens examining the ruins after the Chibok schoolgirls kidnapping; Bundles of wat ...
.
On May 27, the
National Oceanic and Atmospheric Administration
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...
's
Climate Prediction Center
The Climate Prediction Center (CPC) is a United States federal agency that is one of the National Centers for Environmental Prediction, which are a part of the National Oceanic and Atmospheric Administration's National Weather Service. CPC is hea ...
(CPC) released its forecast for the year, highlighting a 70% chance of an above-average season with 15–22 named storms, 7–12 hurricanes, 5–8 major hurricanes, and an
accumulated cyclone energy
Accumulated cyclone energy (ACE) is a metric used by various agencies to express the energy released by a tropical cyclone during its lifetime. It is calculating by summing the square of a tropical cyclone's maximum sustained winds, measured ever ...
(ACE) index range of 110–190% of the median. While both organizations cited an intensifying
El Niño
El Niño (; ; ) is the warm phase of the El Niño–Southern Oscillation (ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (approximately between the International Date L ...
as a cause of increased activity, the CPC also highlighted the difference in global sea surface temperature patterns in 2015 versus the 1995–2014 period.
The season ended up exceeding all of these forecasts with 26 named storms, 16 hurricanes, 11 major hurricanes, and an ACE index at more than 200% of the median.
Seasonal summary
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PlotData=
barset:Hurricane width:11 align:left fontsize:S shift:(4,-4) anchor:till
from:28/05/2015 till:04/06/2015 color:C4 text:"Andres (C4)"
from:31/05/2015 till:09/06/2015 color:C4 text:" Blanca (C4)"
from:10/06/2015 till:17/06/2015 color:C1 text:" Carlos (C1)"
from:08/07/2015 till:10/07/2015 color:TS text:"Ela (TS)"
from:10/07/2015 till:12/07/2015 color:TS text:" Halola (TS)"
from:10/07/2015 till:13/07/2015 color:TS text:"Iune (TS)"
from:11/07/2015 till:19/07/2015 color:C4 text:" Dolores (C4)"
from:12/07/2015 till:18/07/2015 color:TS text:"Enrique (TS)"
from:23/07/2015 till:25/07/2015 color:TS text:"Felicia (TS)"
from:27/07/2015 till:30/07/2015 color:TD text:"Eight-E (TD)"
barset:break
from:29/07/2015 till:07/08/2015 color:C2 text:"Guillermo (C2)"
from:06/08/2015 till:14/08/2015 color:C4 text:"Hilda (C4)"
from:16/08/2015 till:17/08/2015 color:TD text:"Eleven-E (TD)"
from:21/08/2015 till:26/08/2015 color:C1 text:"Loke (C1)"
from:22/08/2015 till:01/09/2015 color:C4 text:"Kilo (C4)"
from:25/08/2015 till:05/09/2015 color:C4 text:"Ignacio (C4)"
from:26/08/2015 till:09/09/2015 color:C4 text:"Jimena (C4)"
from:31/08/2015 till:05/09/2015 color:TS text:"Kevin (TS)"
from:05/09/2015 till:10/09/2015 color:C3 text:" Linda (C3)"
from:19/09/2015 till:22/09/2015 color:TS text:"Malia (TS)"
barset:break
from:20/09/2015 till:21/09/2015 color:TD text:"Sixteen-E (TD)"
from:25/09/2015 till:28/09/2015 color:TS text:"Niala (TS)"
from:26/09/2015 till:01/10/2015 color:C1 text:" Marty (C1)"
from:03/10/2015 till:08/10/2015 color:C2 text:"Oho (C2)"
from:03/10/2015 till:04/10/2015 color:TD text:"Eight-C (TD)"
from:09/10/2015 till:15/10/2015 color:TS text:"Nora (TS)"
from:15/10/2015 till:27/10/2015 color:C4 text:"Olaf (C4)"
from:20/10/2015 till:24/10/2015 color:C5 text:" Patricia (C5)"
from:18/11/2015 till:22/11/2015 color:TS text:"Rick (TS)"
from:23/11/2015 till:28/11/2015 color:C4 text:" Sandra (C4)"
barset:break
from:31/12/2015 till:31/12/2015 color:TD text:"Nine-C (TD)"
bar:Month width:5 align:center fontsize:S shift:(0,-20) anchor:middle color:canvas
from:01/05/2015 till:31/05/2015 text:May
from:01/06/2015 till:30/06/2015 text:June
from:01/07/2015 till:31/07/2015 text:July
from:01/08/2015 till:31/08/2015 text:August
from:01/09/2015 till:30/09/2015 text:September
from:01/10/2015 till:31/10/2015 text:October
from:01/11/2015 till:30/11/2015 text:November
from:01/12/2015 till:31/12/2015 text:December
from:01/01/2016 till:31/01/2016 text:January 2016
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text:"(From the"
pos:(617,30)
text:"Saffir–Simpson scale
The Saffir–Simpson hurricane wind scale (SSHWS) classifies hurricanes—which in the Western Hemisphere are tropical cyclones that exceed the intensities of tropical depressions and tropical storms—into five categories distinguished by ...
)"
The
accumulated cyclone energy
Accumulated cyclone energy (ACE) is a metric used by various agencies to express the energy released by a tropical cyclone during its lifetime. It is calculating by summing the square of a tropical cyclone's maximum sustained winds, measured ever ...
(ACE) index for the 2015 Pacific hurricane season (Eastern Pacific and Central Pacific combined) as calculated by Colorado State University using data from the National Hurricane Center was 290.2 units. ACE is a rough measure of the energy generated by a tropical or subtropical cyclone over its lifespan, and is calculated every six hours when the tropical cyclone has
sustained wind speeds of at least of . Therefore, more intense and longer-lived tropical cyclones will generate more ACE, while tropical depressions are excluded from ACE calculations.
![Pacific SST anomaly 10-15-2015](https://upload.wikimedia.org/wikipedia/commons/4/49/Pacific_SST_anomaly_10-15-2015.gif)
Overall, 31 tropical cyclones formed, of which 26 reached tropical storm intensity and were
named. A total of 16 of these storms became hurricanes, and a record-breaking 11 became major hurricanes. These values make the 2015 season the second-most active on record. The Central Pacific, meanwhile, had its most active year on record, with 16 tropical cyclones forming in or entering the basin, easily surpassing the old record of 11 set in
1992
File:1992 Events Collage V1.png, From left, clockwise: 1992 Los Angeles riots, Riots break out across Los Angeles, California after the Police brutality, police beating of Rodney King; El Al Flight 1862 crashes into a residential apartment buildi ...
and
1994
File:1994 Events Collage.png, From left, clockwise: The 1994 Winter Olympics are held in Lillehammer, Norway; The Kaiser Permanente building after the 1994 Northridge earthquake; A model of the MS Estonia, which Sinking of the MS Estonia, sank in ...
.
The season officially began on May 15 in the Eastern Pacific, and on June 1 in the Central Pacific; the season ended officially on November 30,
though a tropical depression formed well after that on December 31.
The well-above-average activity levels were largely attributed to the strong
2014–16 El Niño event, which brought anomalously high
sea surface temperature
Sea surface temperature (SST), or ocean surface temperature, is the ocean temperature close to the surface. The exact meaning of ''surface'' varies according to the measurement method used, but it is between and below the sea surface. Air mass ...
s and low
vertical wind shear
Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal ...
to western parts of the basin.
In fact, for the region between the
116th meridian west
The meridian 116° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 116th meridian west forms a grea ...
and the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
, sea surface temperatures from July to October averaged , the highest value on record since reliable data records began in 1979.
Around Hawaii, sea surface temperatures were 0.9 °C (1.6 °F) higher than at any point during the past 60 years.
Wind shear in the region was also at its lowest on record during that period.
The existence of a large region of rising air over the basin during much of the season, a feature typical of El Niño events, further facilitated the development and intensification of the season's numerous tropical cyclones.
The season started off with three successive hurricanes, with Andres and Blanca both reaching Category 4 status. On June 3, Blanca became both earliest second hurricane and second major hurricane in the basin since reliable records began in 1971, and became the earliest instance of a
landfall
Landfall is the event of a storm moving over land after being over water. More broadly, and in relation to human travel, it refers to 'the first land that is reached or seen at the end of a journey across the sea or through the air, or the fact ...
on the
Baja California Peninsula.
Ten days later, Carlos became the second-earliest third hurricane on record. After about a month of inactivity, eight systems formed in July, including five from July 8–12. Ela became the earliest named storm to form in the Central Pacific within the bounds of the official season, and along with Iune and Halola, marked the first month in the satellite era where three tropical cyclones were observed in the Central Pacific. Six more systems formed in an active August. Early on August 30, Hurricanes Kilo, Ignacio and Jimena intensified into Category 4 hurricanes. This was the first time in the historical record that three or more major hurricanes existed simultaneously in the Pacific east of the International Date Line, and that two or more major hurricanes existed simultaneously in the Central Pacific.
[
]
![Kilo, Ignacio and Jimena 2015-08-30 2100Z](https://upload.wikimedia.org/wikipedia/commons/e/e2/Kilo%2C_Ignacio_and_Jimena_2015-08-30_2100Z.jpg)
September saw the formation of five systems, excluding Kevin which was named in September but formed on August 31.
Three systems—Linda, Sixteen-E, and Marty—affected Mexico, with the first two also bringing floods to the
Southwestern United States
The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...
.
The flood event caused by Linda in
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
was also the state's deadliest.
October saw another five systems. With the formation of Oho on October 3, the 2015 season surpassed 1992 and 1994 as the most active year on record in the Central Pacific.
During October 18–19, Olaf became the southernmost-forming hurricane and major hurricane in the Eastern Pacific.
Olaf later became the first system on record to cross from the Eastern Pacific into the Central Pacific and then back into the Eastern Pacific while still a tropical cyclone.
Patricia
Patricia is a female given name of Latin language, Latin origin. Derived from the Latin word ''Patrician (ancient Rome), patrician'', meaning "noble"; it is the feminine form of the masculine given name Patrick (given name), Patrick. The name Patr ...
became the strongest hurricane in the basin on October 23 when its
pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and e ...
fell to 892
mbar
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea leve ...
(
hPa HPA may refer to:
Organizations
* Harry Potter Alliance, a charity
* Halifax Port Authority, Canada
* Hamburg Port Authority, Germany
* Hawaii Preparatory Academy, a school in Hawaii, US
* Health Protection Agency, UK
* Heerespersonalamt, the Ger ...
; 26.34
inHg
Inch of mercury (inHg and ″Hg) is a non- SI unit of measurement for pressure. It is used for barometric pressure in weather reports, refrigeration and aviation in the United States.
It is the pressure exerted by a column of mercury in heigh ...
), breaking the previous record of 902 mbar (hPa; ) set by
1997
File:1997 Events Collage.png, From left, clockwise: The movie set of ''Titanic'', the highest-grossing movie in history at the time; ''Harry Potter and the Philosopher's Stone'', is published; Comet Hale-Bopp passes by Earth and becomes one of t ...
's
Hurricane Linda. Patricia subsequently became the strongest tropical cyclone on record in the
Western Hemisphere
The Western Hemisphere is the half of the planet Earth that lies west of the prime meridian (which crosses Greenwich, London, United Kingdom) and east of the antimeridian. The other half is called the Eastern Hemisphere. Politically, the term We ...
in terms of barometric pressure, with a central pressure of 872 mbar (hPa; ). This value was also the second-lowest globally, behind
Typhoon Tip
Typhoon Tip, known in the Philippines as Typhoon Warling, was the largest and most intense tropical cyclone ever recorded. The forty-third tropical depression, nineteenth tropical storm, twelfth typhoon, and third super typhoon of the 1979 Paci ...
of 1979 which had a central pressure of 870 mbar (hPa; ). Additionally, its maximum sustained winds of were the strongest ever reliably recorded or estimated anywhere globally.
Patricia later became the strongest Pacific hurricane to strike Mexico after making landfall in
Jalisco
Jalisco (, , ; Nahuatl: Xalixco), officially the Free and Sovereign State of Jalisco ( es, Estado Libre y Soberano de Jalisco ; Nahuatl: Tlahtohcayotl Xalixco), is one of the 31 states which, along with Mexico City, comprise the 32 Federal En ...
as a strong Category 4 hurricane.
The following month tied for the most active November with the development of two systems, Rick and Sandra.
Sandra subsequently strengthened into a major hurricane, bringing the season total to a record 11.
Its peak winds of and minimum central pressure of 934 mbar (hPa; ) surpassed
Hurricane Kenneth The name Kenneth has been used for four tropical cyclones in the Eastern Pacific Ocean and one in the South-West Indian Ocean.
In the Eastern Pacific:
* Hurricane Kenneth (1993) – Category 4 hurricane that did not affect land.
* Hurricane Ke ...
of 2011 for the strongest November Pacific hurricane in terms of both sustained winds and central pressure.
Despite the official end of the season on November 30,
anomalously favorable conditions in the Central Pacific gave rise to the final storm of the season, Tropical Depression Nine-C, which formed on December 31 and dissipated late the same day.
This marked the latest end to a Pacific hurricane season on record.
Systems
Hurricane Andres
On May 23, the
National Hurricane Center
The National Hurricane Center (NHC) is the division of the United States' NOAA/National Weather Service responsible for tracking and predicting tropical weather systems between the Prime Meridian and the 140th meridian west poleward to the 3 ...
(NHC) began monitoring the potential for tropical cyclogenesis well south of Mexico over the following days. A broad
low-pressure area
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible ...
formed three days later, steadily organizing to become Tropical Depression One-E at 06:00
UTC on May 28.
With an increase in
spiral banding and an expanding
central dense overcast
The central dense overcast, or CDO, of a tropical cyclone or strong subtropical cyclone is the large central area of thunderstorms surrounding its circulation center, caused by the formation of its eyewall. It can be round, angular, oval, or irr ...
, the depression was upgraded to Tropical Storm Andres six hours later. Directed west-northwest and eventually northwest by a subtropical
ridge
A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...
over Mexico, the cyclone quickly organized and became a hurricane on May 29. A spurt of intensification saw Andres strengthen into a strong Category 2 hurricane late the next day. Andres's intensification trend leveled off thereafter due to an
eyewall replacement cycle
In meteorology, eyewall replacement cycles, also called concentric eyewall cycles, naturally occur in intense tropical cyclones, generally with winds greater than , or major hurricanes ( Category 3 or above). When tropical cyclones reach this int ...
and a brief increase in
vertical wind shear
Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal ...
, but Andres still managed to reach major hurricane status early on May 31, becoming one of only five major hurricanes during the month of May.
Although forecasts did not indicate additional strengthening, Andres began a period of
rapid deepening
In meteorology, rapid intensification is a situation where a tropical cyclone intensifies dramatically in a short period of time. The United States National Hurricane Center defines rapid intensification as an increase in the maximum sustained ...
the following day as wind shear decreased, intensifying into a Category 4 hurricane at 00:00 UTC on June 1. Andres reached its peak intensity six hours later with
maximum sustained wind
The maximum sustained wind associated with a tropical cyclone is a common
indicator of the intensity of the storm. Within a mature tropical cyclone, it is found within the eyewall at a distance defined as the radius of maximum wind, or RMW. Unl ...
s of and a
minimum pressure of 937
mbar
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea leve ...
(
hPa HPA may refer to:
Organizations
* Harry Potter Alliance, a charity
* Halifax Port Authority, Canada
* Hamburg Port Authority, Germany
* Hawaii Preparatory Academy, a school in Hawaii, US
* Health Protection Agency, UK
* Heerespersonalamt, the Ger ...
; 27.67
inHg
Inch of mercury (inHg and ″Hg) is a non- SI unit of measurement for pressure. It is used for barometric pressure in weather reports, refrigeration and aviation in the United States.
It is the pressure exerted by a column of mercury in heigh ...
).
Thereafter, the system moved west-northwestwards over cooler waters and into a more stable environment, which led to a swift weakening trend. Andres fell below hurricane strength on the morning of June 2, and weakened into a tropical storm a day later. Further weakening ensued as
convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...
around Andres's center dissipated,
and the NHC declared Andres a remnant low on June 4.
Moisture extending from the remnants of Andres brought light rain to parts of the
Southwest United States
The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...
, with
Phoenix, Arizona
Phoenix ( ; nv, Hoozdo; es, Fénix or , yuf-x-wal, Banyà:nyuwá) is the List of capitals in the United States, capital and List of cities and towns in Arizona#List of cities and towns, most populous city of the U.S. state of Arizona, with 1 ...
having measurable precipitation on June 5 for the first time since records began in 1896. This moisture further extended into
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
, resulting in scattered severe thunderstorms.
Hurricane Blanca
A
tropical wave
A tropical wave (also called easterly wave, tropical easterly wave, and African easterly wave), in and around the Atlantic Ocean, is a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which ...
first monitored by the NHC late on May 27 spawned a weak low-pressure area well south of
Acapulco, Mexico
Acapulco de Juárez (), commonly called Acapulco ( , also , nah, Acapolco), is a city and major seaport in the state of Guerrero on the Pacific Coast of Mexico, south of Mexico City. Acapulco is located on a deep, semicircular bay and has bee ...
, two days later. Plagued by strong upper-level winds from Hurricane Andres, the disturbance slowly organized into the season's second tropical depression at 12:00 UTC on May 31 and further into Tropical Storm Blanca on the following day. Moving little within a weak steering regime, the cyclone began to rapidly deepen by June 2 as conditions aloft became more favorable; following the appearance of a pinhole eye, Blanca became a major hurricane at 12:00 UTC on June 3. Shortly thereafter, Blanca reached its peak intensity as a Category 4 hurricane with winds of and a pressure of 936 mbar (hPa; 27.64 inHg).
Tremendous
upwelling
Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted surface water. The nutr ...
of cooler waters, with some areas falling from ,
resulted in weakening early on June 4. A concurrent eyewall replacement cycle spurred further weakening and Blanca degraded to Category 1 status by June 5. The next day, a shifting
ridge
A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...
steered Blanca northwest back over warm waters, allowing Blanca to quickly reintensify to a secondary peak of . However, as Blanca tracked poleward, waters beneath the cyclone cooled yet again, prompting a quick weakening trend. After weakening to a tropical storm on June 7, Blanca made
landfall
Landfall is the event of a storm moving over land after being over water. More broadly, and in relation to human travel, it refers to 'the first land that is reached or seen at the end of a journey across the sea or through the air, or the fact ...
around 12:00 UTC on June 8, near
Puerto Cortés
Puerto Cortés, originally known as Puerto de Caballos, is a port city and municipality on the north Caribbean coast of Honduras, right on the Laguna de Alvarado, north of San Pedro Sula and east of Omoa, with a natural bay. The present city ...
with winds of ,
and became the earliest instance of a landfall in the
Baja California Peninsula since records began in 1949.
Swiftly weakening over land, Blanca degenerated to a remnant low on June 9 and dissipated shortly after.
On June 3, precautionary alerts were raised across the southern Baja California Peninsula and much of Western Mexico, due to potential impacts from the hurricane. A collective 3,300 troops from the Mexican Army and Navy were deployed to
Baja California Sur
Baja California Sur (; 'South Lower California'), officially the Free and Sovereign State of Baja California Sur ( es, Estado Libre y Soberano de Baja California Sur), is the least populated state and the 31st admitted state of the 32 federal ent ...
to ensure the safety of residents. Although Blanca remained far from
Jalisco
Jalisco (, , ; Nahuatl: Xalixco), officially the Free and Sovereign State of Jalisco ( es, Estado Libre y Soberano de Jalisco ; Nahuatl: Tlahtohcayotl Xalixco), is one of the 31 states which, along with Mexico City, comprise the 32 Federal En ...
, large
swells and
rip current
A rip current, often simply called a rip (or misleadingly a ''rip tide''), is a specific kind of water current that can occur near beaches with breaking waves. A rip is a strong, localized, and narrow current of water which moves directly away ...
s produced by the hurricane claimed four lives. Across Baja California Sur, high winds downed power lines and left 104,106 residents without electricity. However, around 90 percent of the outages were fixed within 12 hours of the storm. The remnants of Blanca later brought much-needed rain to parts of the Southwestern United States. Daily rainfall records were broken in several areas, though accumulations were generally less than . Some flooding took place in
Santa Barbara County, California
Santa Barbara County, California, officially the County of Santa Barbara, is located in Southern California. As of the 2020 census, the population was 448,229. The county seat is Santa Barbara, and the largest city is Santa Maria.
Santa Barba ...
. Flash floods across
Nevada
Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...
inundated homes and roads, and also caused minor damage to landscaping. In
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
, strong thunderstorms brought hail of up to in diameter, and spawned a brief
EF0
The Enhanced Fujita scale (abbreviated as EF-Scale) rates tornado intensity based on the severity of the damage they cause. It is used in some countries, including the United States, Canada, China, and Mongolia.
The Enhanced Fujita scale repla ...
tornado
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, altho ...
near
Napi Headquarters. Damage across California amounted to $68,000, while damage across Nevada totaled $46,000. Damage in New Mexico reached $20,000. Additionally, on June 10, some of Blanca's moisture moved north and brought light showers to the
San Francisco Bay Area
The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...
.
Hurricane Carlos
In early June, a
Kelvin wave
A Kelvin wave is a wave in the ocean or atmosphere that balances the Earth's Coriolis force against a topographic boundary such as a coastline, or a waveguide such as the equator. A feature of a Kelvin wave is that it is non-dispersive, i.e., the ...
interacted with a few tropical waves to the south of Mexico. The system gradually organized and was designated as a tropical depression on June 10, while situated about south-southeast of
Puerto Escondido, Oaxaca
Puerto Escondido (English: "Hidden Port") is a small port and tourist center in the municipality of San Pedro Mixtepec Distrito 22 in the Mexican state of Oaxaca. Prior to the 1930s, there was no town. The bay had been used as a port intermittent ...
. Drifting slowly northwestward, the depression was upgraded further to tropical storm intensity. Although persistent wind shear and dry air hampered intensification early on, Carlos strengthened into a hurricane on June 13 after moving into more favorable conditions. However, the return of dry air and upwelling caused the storm to deteriorate into a tropical storm. Paralleling the Mexican coast, Carlos regained hurricane intensity on June 15 and peaked with sustained winds of and a pressure of 978 mbar (hPa; 28.88 inHg) the next day. Wind shear and dry air afterwards caused Carlos to rapidly weaken, falling to tropical storm intensity on June 17 and degenerating into a remnant low-pressure area hours later.
Carlos' formation prompted coastal authorities to enact precautionary measures along states deemed at risk. In
Guerrero
Guerrero is one of the 32 states that comprise the 32 Federal Entities of Mexico. It is divided in 81 municipalities and its capital city is Chilpancingo and its largest city is Acapulcocopied from article, GuerreroAs of 2020, Guerrero the pop ...
, 507 shelters were opened.
The NHC also issued several
tropical cyclone warnings and watches
Tropical cyclone warnings and watches are alerts issued by national weather forecasting bodies to coastal areas threatened by the imminent approach of a tropical cyclone of tropical storm or hurricane intensity. They are notices to the local popul ...
between June 11 and June 17 from Jalisco to Guerrero. Rough seas along the shore generated by the hurricane caused widespread damage.
Twelve ships, including a yacht worth 11 million
pesos
The peso is the monetary unit of several countries in the Americas, and the Philippines. Originating in the Spanish Empire, the word translates to "weight". In most countries the peso uses the same sign, "$", as many currencies named "dollar" ...
(US$717,000), sunk in Playa Manzanillo harbor. The waves, along with heavy rain, inflicted at least 5 million pesos (US$326,000) of damage on
Michoacán
Michoacán, formally Michoacán de Ocampo (; Purépecha: ), officially the Free and Sovereign State of Michoacán de Ocampo ( es, Estado Libre y Soberano de Michoacán de Ocampo), is one of the 32 states which comprise the Federal Entities of ...
's coastal installations.
Strong winds produced by the passing storm also downed trees, power poles, and billboards, especially in Acapulco. There, 16 homes were swept away by the waves.
Tropical Storm Ela
A tropical wave crossing the Eastern Pacific spawned a low-pressure area on July 3.
The system gradually organized amid persistent wind shear and on July 8, the system intensified into Tropical Depression Four-E just before it entered the area of responsibility of the
Central Pacific Hurricane Center
The Central Pacific Hurricane Center (CPHC) of the United States National Weather Service is the official body responsible for tracking and issuing tropical cyclone warnings, watches, advisories, discussions, and statements for the Central Pacifi ...
(CPHC). On July 9, the depression intensified into a tropical storm as it tracked to the northwest, and was named ''Ela'' by the CPHC. Ela intensified slightly to reach its peak intensity with winds of and a pressure of 1002 mbar (hPa; 29.59 inHg), however, strong wind shear prevented Ela from intensifying further by removing thunderstorms from the circulation center, and eventually causing it to gradually weaken. Ela was downgraded to a depression on July 10, and not long after declared a remnant low well east of the
Hawaiian Islands
The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kur ...
.
Ela is one of just seven tropical cyclones to form as a depression in the Eastern Pacific basin but not be named until entering the Central Pacific; the others are
Lala
Lala may refer to:
Geography
* Lala language (disambiguation) Places
* Lala (Naples Metro), an underground metro station in Naples, Italy
* Lala, Assam, a town in Assam, India
* Lala, Ilam, a village in Ilam Province, Iran
* Lala, Lanao del No ...
,
Li,
Iniki and
Lana
Lana may refer to:
*Lana (given name)
*Francesco Lana de Terzi (1631–1687), Italian Jesuit priest and scientist
*Lana (wrestler), professional wrestler and pro wrestling manager
*''Wild Energy. Lana'', a 2006 Ukrainian fantasy novel
Sciences
*L ...
, and
Akoni
Tariqh Akoni is a performing and session guitarist and songwriter based in Los Angeles, California. He is the former Chair of the Guitar Department at the Los Angeles Music Academy College of Music, L.A. Music Academy (succeeding Frank Gambale) as ...
. It would be succeeded by
Hurricane Ulika a year later. It is also the fourth earliest storm to form during the calendar year in the Central Pacific after
Ekeka and
Hali
Hali may refer to:
*Hali I of the Maldives (died 1268), Sultan of Maldives from 1266 to 1268
* Hali II of the Maldives (died 1288), Sultan of Maldives from 1278 to 1288
*a medieval Latinisation of Arabic Ali (also ''Haly'')
** Haly Abenragel, com ...
of 1992,
as well as
Pali
Pali () is a Middle Indo-Aryan liturgical language native to the Indian subcontinent. It is widely studied because it is the language of the Buddhist ''Pāli Canon'' or ''Tipiṭaka'' as well as the sacred language of ''Theravāda'' Buddhism ...
of 2016.
Tropical Storm Halola
A
monsoon trough
The monsoon trough is a portion of the Intertropical Convergence Zone in the Western Pacific,Bin WangThe Asian Monsoon.Retrieved 2008-05-03. as depicted by a line on a weather map showing the locations of minimum sea level pressure, and as such, ...
building across the Pacific Ocean spawned a large, ill-defined circulation well southwest of Hawaii on July 3. The circulation organized slightly and began to detach from the monsoon trough on July 6, but further development was halted for a while as an upper-level
anticyclone
An anticyclone is a weather phenomenon defined as a large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere as viewed from abov ...
imparted strong wind shear over the system. The anticyclone moved away on July 9, allowing the low-level circulation to move under the persistent convection to the northwest. As thunderstorm activity expanded in coverage, the system was declared Tropical Depression One-C by the CPHC at 06:00 UTC on July 10. Moving westwards under the influence a strong ridge to the north, the depression slowly strengthened into Tropical Storm Halola early on July 11. After intensifying to reach winds of , a slight increase in wind shear prevented further strengthening. Maintaining that intensity, Halola crossed the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
into the
Western Pacific basin late on July 12, and entered the area of responsibility of the
Japan Meteorological Agency
The , abbreviated JMA, is an agency of the Ministry of Land, Infrastructure, Transport and Tourism. It is charged with gathering and providing results for the public in Japan that are obtained from data based on daily scientific observation an ...
.
Tropical Storm Iune
A weak low-pressure area was first identified in the monsoon trough southeast of Hawaii on July 2. It drifted west-northwest, gradually becoming better defined as thunderstorm activity increased and it separated from the monsoon trough; by 06:00 UTC on July 10, there was sufficient organization to declare it a tropical depression. The small size of the cyclone made it especially susceptible to moderate upper-level winds, and it failed to intensify to Tropical Storm Iune until 18:00 UTC on July 11, when deep convection persisted near the center. No further intensification occurred amid light southerly wind shear, and Iune weakened to a tropical depression around 18:00 UTC on July 12 as it moved west-southwest. After being devoid of thunderstorm activity for 18 hours, the storm degenerated to a remnant low by 12:00 UTC the next day. The post-tropical cyclone moved west across the Central Pacific before finally dissipating around 12:00 UTC on July 17.
Hurricane Dolores
A westward-moving tropical wave crossed Central America and entered the Eastern Pacific on July 9. On July 11, the system was declared Tropical Depression Five-E while located roughly south-southeast of Acapulco, Mexico. Amid moderate northwesterly wind shear, the depression gradually strengthened into Tropical Storm Dolores and reached hurricane status on July 13. As Dolores moved roughly parallel to the coast of Mexico, the shear over the system decreased, allowing for a burst of rapid intensification. Dolores peaked as a Category 4 hurricane with winds of and a minimum pressure of 946 mbar (hPa; ) early on July 15. However, as Dolores approached
Socorro Island
Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest ...
, the cyclone underwent an eyewall replacement cycle and began to steadily weaken. The storm remained potent though as it passed Socorro Island, with an automated weather station on the island recording sustained hurricane-force winds. Despite completing the cycle on July 16, Dolores had moved over cooler
sea surface temperatures
Sea surface temperature (SST), or ocean surface temperature, is the ocean temperature close to the surface. The exact meaning of ''surface'' varies according to the measurement method used, but it is between and below the sea surface. Air masse ...
, and hence continued its weakening trend. By the morning of July 17, Dolores had deteriorated to a tropical storm, and eventually degenerated into a post-tropical remnant low about west of the Baja California coast the next day. The remnant low slowly curved southwards and dissipated on July 22 well west of
San Diego
San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...
.
Moisture extending from the storm's remnants brought record rains and thunderstorms to
Southern California
Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...
; record monthly rainfall totals include in San Diego, in Los Angeles, and in
Paso Robles
Paso Robles ( ), officially El Paso de Robles (Spanish for "The Pass of Oaks"), is a city in San Luis Obispo County, California, United States. Located on the Salinas River approximately north of San Luis Obispo, the city is known for its hot ...
. In the foothills and mountains of east
San Diego County
San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the fi ...
, rainfall exceeded . This had the effect of helping firefighters contain the
North Fire
The North Fire was a wildfire that occurred in the Mojave Desert near the towns of Victorville and Hesperia, north of San Bernardino and south of Bakersfield, California. The fire began on July 17, 2015. The areas most impacted were adjacent to ...
, but also resulted in debris flows and rock slides that damaged about 90 homes and submerged cars.
The San Diego River reached levels of —just below flood stage—and overflowed its banks in a few areas.
Flash flooding occurred in
Moreno Valley
Moreno Valley is a city in Riverside County, California, United States, and is part of the Riverside–San Bernardino–Ontario metropolitan area. It is the second-largest city in Riverside County by population and one of the Inland Empire's po ...
,
Perris
Perris is an old railway city in Riverside County, California, United States, located east-southeast of Los Angeles and north of San Diego. It is known for Lake Perris, an artificial lake, skydiving, and its sunny dry climate. Perris is wit ...
, and
La Mesa, while a
microburst occurred in
Tierrasanta
Tierrasanta, Spanish for "holy land," or "holy ground", is a community within the city of San Diego, California. The symbol of Tierrasanta is an encircled Conquistador cross, similar to one atop Montserrat (mountain) near Barcelona, Spain, though ...
. A
haboob
A haboob ( ar, هَبوب, lit=blasting/drifting, translit=habūb) is a type of intense dust storm carried on an atmospheric gravity current, also known as a weather front. Haboobs occur regularly in dry land area regions throughout the world.
...
was also recorded in
Anza-Borrego Desert State Park
Anza-Borrego Desert State Park (, '' AN-zə bə-RAY-goh'') is a California State Park located within the Colorado Desert of southern California, United States. The park takes its name from 18th century Spanish explorer Juan Bautista de Anza and ...
. Strong winds blew over a
semi truck
A semi-trailer truck, also known as a semitruck, (or semi, eighteen-wheeler, big rig, tractor-trailer or, by synecdoche, a semitrailer) is the combination of a tractor unit and one or more semi-trailers to carry freight. A semi-trailer a ...
as well as power poles and lines on
Interstate 40
Interstate 40 (I-40) is a major east–west Interstate Highway running through the south-central portion of the United States. At a length of , it is the third-longest Interstate Highway in the country, after I-90 and I-80. From west to ea ...
near the California-Nevada border, obstructing the road in both directions and causing $75,000 in damage. In
Kern County
Kern County is a county located in the U.S. state of California. As of the 2020 census, the population was 909,235. Its county seat is Bakersfield.
Kern County comprises the Bakersfield, California, Metropolitan statistical area. The county sp ...
, a 62-year-old man was killed by a lightning strike. A bridge along
Interstate 10
Interstate 10 (I-10) is the southernmost cross-country highway in the American Interstate Highway System. I-10 is the fourth-longest Interstate in the United States at , following I-90, I-80, and I-40. This freeway is part of the originally pl ...
near
Desert Center
Desert Center is a census designated place in the Colorado Desert in Riverside County, California. It is in southern California, between the cities of Indio and Blythe at the junction of Interstate 10 and State Route 177, about halfway between Pho ...
was washed out, injuring one. Damage to the bridge was placed at $50 million. Another road was washed out by flash flooding, this time along
State Route 78 southwest of
Cibola, Arizona
Cibola is a census-designated place (CDP) in La Paz County, Arizona, United States. The population was 250 at the 2010 census, up from 172 in 2000. It is named for the famed city of gold of the same name.
Geography
Cibola is located in southw ...
, with damage totaling $50,000. Hail the size of golf balls was recorded in
Bear Valley, Alpine County, damaging a police vehicle. Losses across California reached $50.477 million.
Tropical Storm Enrique
A tropical wave about 1,150 mi (1,850 km) southwest of the tip of the Baja California Peninsula spawned a broad low-pressure area on July 10. The low's circulation became increasingly well-defined as the tropical wave moved away from the system, leading to the classification of Tropical Depression Six-E at 12:00 UTC on July 12. Gradually organizing as it crawled west-northwestwards, the depression intensified to become Tropical Storm Enrique 18 hours later. Despite being situated in a generally favorable environment, dry air to the northwest of Enrique entrained into its circulation, causing the system to struggle to intensify. Eventually, the system reached its peak intensity late on July 14 with winds and a minimum pressure of 1,000 mbar (hPa; ). Thereafter, increasing southwesterly vertical wind shear threatened to expose the low-level circulation, and Enrique started to weaken on July 15. Despite moving over cooler waters, Enrique maintained its intensity over the next two days as it began to slow down and turn to the southwest under the influence of Hurricane Dolores to its east. During the afternoon of July 17, Enrique weakened to a tropical depression, and degenerated to a remnant low the next day. The remnants curved back to the east over the next few days, dissipating entirely well west of the Baja California Peninsula by July 22.
Tropical Storm Felicia
A westward-tracking tropical wave moved off Africa on July 7, crossing into the East Pacific nine days later. The disturbance was initially disorganized, with a broad, elongated circulation and intermittent convection; by 06:00 UTC on July 23, however, it acquired sufficient organization to be declared a tropical depression about southwest of Baja California. Six hours later, the depression intensified into Tropical Storm Felicia and attained peak intensity with winds of and a pressure of 1004 mbar (hPa; 29.65 inHg). The negative effects of shear, dry air, and cooler waters began to affect Felicia almost immediately, and the cyclone weakened to a tropical depression by 00:00 UTC on July 24. All associated convection with the storm dissipated by 18:00 UTC that day, marking Felicia's degeneration into a remnant low west of the southern tip of Baja California. The low turned west and southwest prior to opening into a trough on July 28.
Tropical Depression Eight-E
A tropical wave accompanied by showers and thunderstorms entered the Eastern Pacific Ocean on July 19. Tracking steadily westwards, the wave formed a low-pressure area in the middle of the Eastern Pacific on July 27. Turning slightly to the west-northwest, the low slowly intensified into Tropical Depression Eight-E six hours later. However, strong north-northwesterly wind shear prevented it from intensifying into a tropical storm. As Eight-E moved into a drier environment, it failed to sustain deep convection near its center, and eventually degenerated into a remnant low late on July 29. Eight-E's remnants continued tracking in a westward direction and opened up into a trough by August 1 well east-southeast of Hawaii.
Hurricane Guillermo
A tropical disturbance well south of the Baja California Peninsula gained enough organization to be declared Tropical Depression Nine-E on July 29. Located in an environment of low wind shear, high sea surface temperatures and abundant moisture, conditions were very favorable for strengthening, allowing Nine-E to intensify into Tropical Storm Guillermo just six hours later. Continuing to quickly intensify while tracking steadily west-northwestwards, Guillermo became a hurricane only 36 hours after its formation, and eventually reached peak intensity with winds of and a pressure of 967 mbar (hPa; 28.56 inHg)—a strong Category 2 hurricane. Guillermo weakened slightly afterwards, but remained at Category 2 strength as it crossed
140°W into the Central Pacific late on August 1. However, as Guillermo neared
Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...
, increasing southwesterly wind shear began to weaken the cyclone, and Guillermo eventually degraded to a tropical storm on August 3. Wobbling towards the west-northwest following a break in the subtropical ridge, Guillermo weakened further to a tropical depression on August 7, located north of
Maui
The island of Maui (; Hawaiian: ) is the second-largest of the islands of the state of Hawaii at 727.2 square miles (1,883 km2) and is the 17th largest island in the United States. Maui is the largest of Maui County's four islands, which ...
. Not long after, Guillermo degenerated to a post-tropical low, and dissipated altogether by August 9.
On August 6, some of Guillermo's moisture was brought to
Northern California
Northern California (colloquially known as NorCal) is a geographic and cultural region that generally comprises the northern portion of the U.S. state of California. Spanning the state's northernmost 48 counties, its main population centers incl ...
and the San Francisco Bay Area by the
jet stream
Jet streams are fast flowing, narrow, meandering thermal wind, air currents in the Atmosphere of Earth, atmospheres of some planets, including Earth. On Earth, the main jet streams are located near the altitude of the tropopause and are west ...
, bringing rare
dry lightning
A dry thunderstorm is a thunderstorm that produces thunder and lightning, but where most of its precipitation evaporates before reaching the ground. Dry lightning refers to lightning strikes occurring in this situation. Both are so common in the ...
storms to those areas during the night.
Hurricane Hilda
A tropical wave behind Guillermo spawned a well-defined low-pressure area well to the west of Mexico, which became Tropical Depression Ten-E on August 5. The depression intensified into Tropical Storm Hilda the next day. Amid moderate northeasterly wind shear and warm waters, Hilda gradually strengthened into a hurricane on August 7 while moving steadily westwards. Rapid intensification ensued thereafter as the shear diminished and a small inner core developed, and Hilda became a major hurricane just before entering the Central Pacific. Continuing to rapidly intensify, Hilda eventually reached its peak intensity as a Category 4 hurricane late on August 8, possessing sustained winds and a minimum pressure of 937 mbar (hPa; ). Hilda then moved over slightly cooler waters and into a drier environment, resulting in a weakening trend that saw Hilda drop below major hurricane status late on August 9. The next two days saw Hilda turn to the northwest and slow down while rounding the southwestern part of a subtropical ridge. Weakening continued and accelerated on August 10–11 as the subtropical jet stream over Hawaii inflicted strong wind shear over Hilda, exposing the low-level circulation. Under the influence of both the strong westerly jet stream and the easterly trade winds, Hilda became almost stationary as it rapidly dropped below hurricane strength on August 12. Convection over Hilda mostly dissipated by August 13, and the shallower system began to track to the west-southwest. Hilda degenerated to a remnant low south of Hawaii by August 14,
after bringing heavy rain to the
Big Island.
Tropical Depression Eleven-E
A broad low-pressure area around south-southwest of
Cabo San Lucas
Cabo San Lucas (, "Saint Luke Cape"), or simply just Cabo, is a resort city at the southern tip of the Baja California Peninsula, in the Mexican state of Baja California Sur. As at the 2020 Census, the population of the city was 202,694 inhabitan ...
organized into Tropical Depression Eleven-E on August 16. Moving on a northwesterly to west-northwesterly path, the cyclone failed to intensify due to its large circulation and entered an area of unfavorable conditions late on August 17. Southeasterly shear, dry air entrainment, and cooler waters caused the depression to lose its deep convection and eventually degenerate into a remnant low by August 18. The low turned to the north-northwest and dissipated into a trough two days later around 980 mi (1,575 km) west of
Punta Eugenia
Punta Eugenia is a headland in the Mulegé Municipality. It marks the Western tip of the Vizcaíno Peninsula, thus being the westernmost point on the mainland of the state of Baja California Sur. It belongs to the larger area of El Vizcaíno Biosp ...
.
Hurricane Loke
A low-level trough developed along the
Intertropical Convergence Zone
The Intertropical Convergence Zone (ITCZ ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal e ...
southeast of Hawaii on August 13. It merged with the remnants of Hurricane Hilda into the monsoon trough by August 18, and continued west with intermittent bursts of convection. One such burst detached a well-defined circulation from the monsoon trough and pulled it northeastwards, leading to the formation of a tropical depression by 00:00 UTC on August 21, which became Tropical Storm Loke later that day. A nearby upper-level trough restricted the outflow of the storm shortly after formation, causing it to briefly weaken to a tropical depression early on August 22 while it moved in an undulating fashion. However, as Loke accelerated to the northeast with the trough positioned to the northwest, the upper-level environment became more favorable, and the system regained tropical storm strength early on August 23. Developing a cloud-filled eye, Loke reached hurricane intensity around 18:00 UTC on August 24, simultaneously peaking with winds of and a pressure of 985 mbar (hPa; 29.09 inHg). Afterwards, Loke was once again hindered by the aforementioned nearby trough, which served to impart strong wind shear over the system and pull it to the north. The cyclone weakened to a tropical storm late on August 25 as it underwent
extratropical transition
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth. Extratropical cyclones are capable of p ...
, before it was rapidly drawn northwestwards into the circulation of a large extratropical low (formerly
Typhoon Atsani) by 00:00 UTC on August 27.
Hurricane Kilo
The disturbance that would become Kilo was first noticed by the CPHC within a trough on August 17, located 1,150 mi (1,850 km) southeast of the Big Island of Hawaii. The disturbance produced intermittent thunderstorm activity as it exited the trough on August 19–20. A mid-level ridge steered the disturbance west-northwestwards while imparting easterly wind shear over the system, serving to prevent the disturbance from organizing. Eventually, the shear decreased as the ridge weakened, and the disturbance became a tropical depression with convection near the center of circulation on August 22. During the next two days, the depression turned to the northwest and then the north around the western end of the weakening ridge, all the while remaining rather weak and disorganized. On August 26, however, the development of a new ridge directed the depression towards the southwest and caused the remaining wind shear to decrease. This led to the depression intensifying into Tropical Storm Kilo at 18:00 UTC as the system approached
Johnston Atoll
Johnston Atoll is an Unincorporated territories of the United States, unincorporated territory of the United States, currently administered by the United States Fish and Wildlife Service (USFWS). Johnston Atoll is a National Wildlife Refuge and ...
. Tropical storm warnings were issued for the atoll as Kilo passed within to the north at around 00:00 UTC on August 28.
Amid high sea surface temperatures and low vertical wind shear, Kilo began to quickly strengthen while being steered westwards by a mid-level ridge, attaining hurricane status on August 29. Over the next 24 hours, Kilo rapidly deepened into a Category 4 hurricane, with the winds nearly doubling from to . Kilo reached its peak intensity at the end of this strengthening phase, with the central pressure dropping to 940 mbar (hPa; ). Around this time, Kilo was one of three hurricanes at Category 4 intensity spanning the Eastern and Central Pacific basins, the first such occurrence in recorded history. Thereafter, a slight weakening trend took place, with Kilo dropping to Category 3 status late on August 30. Turning to the northwest through a break in the ridge, Kilo maintained its intensity over the next couple of days as it approached the International Date Line. Between 12:00 UTC and 18:00 UTC on September 1, Kilo crossed the Date Line and entered the jurisdiction of the Japan Meteorological Agency, simultaneously becoming
a typhoon. Kilo continued on as a tropical cyclone until September 10 when it dissipated near the western
Kuril Islands
The Kuril Islands or Kurile Islands (; rus, Кури́льские острова́, r=Kuril'skiye ostrova, p=kʊˈrʲilʲskʲɪjə ɐstrɐˈva; Japanese: or ) are a volcanic archipelago currently administered as part of Sakhalin Oblast in the ...
of Russia, having traversed over 4,000 mi (6,400 km) from its genesis point south of the Hawaii islands.
Hurricane Ignacio
On August 25, a low-pressure system organized into Tropical Depression Twelve-E, before strengthening into Tropical Storm Ignacio later that day. Ignacio initially moved west-northwest, posing a threat to Hawaii. On August 26, Ignacio became a hurricane while continuing its trek towards Hawaii. Over the next few days, Ignacio struggled to intensify while being impacted by moderate wind shear. As wind shear relaxed, Ignacio was able to quickly intensify to major hurricane status on August 29.
At this time, the Big Island of Hawaii was placed under a tropical storm watch, as the island began feeling the effects of high surf. Ignacio continued to rapidly intensify as it turned to the northwest and away from Hawaii, attaining peak intensity at Category 4 status with winds of and a minimum central pressure of 942 mbar (hPa; ) on August 30.
Ignacio was also one of three simultaneous Category 4 Pacific hurricanes east of the International Date Line along with Kilo and Jimena, the first such occurrence in recorded history.
After peaking in intensity, Ignacio began weakening as southwesterly wind shear increased. The system weakened to tropical storm strength at midnight on September 2 well north of Hawaii, but was soon able to reattain hurricane status while passing over anomalously warm waters and experiencing a brief respite in wind shear. Continuing to track northwards over decreasing sea surface temperatures, Ignacio weakened to a tropical storm for the last time on September 3, and became post-tropical late the next day. The remnants of Ignacio continued north across the Pacific, before turning to the east-northeast towards
western Canada
Western Canada, also referred to as the Western provinces, Canadian West or the Western provinces of Canada, and commonly known within Canada as the West, is a Canadian region that includes the four western provinces just north of the Canada ...
on September 6. On September 8, the extratropical remnants of Ignacio were absorbed by a cold front, hundreds of miles south of Alaska.
Hurricane Jimena
A westward-moving low-pressure area organized into a tropical depression on August 26, around 735 mi (1,185 km) southwest of
Manzanillo, Mexico. Moving over very warm waters and located in an environment of low wind shear and abundant moisture, the depression steadily strengthened, becoming Tropical Storm Jimena on August 27. Jimena soon developed a tight inner core, with the
radius of maximum wind
The radius of maximum wind (RMW) is the distance between the center of a cyclone and its band of strongest winds. It is a parameter in atmospheric dynamics and tropical cyclone forecasting. The highest rainfall rates occur near the RMW of tropic ...
s extending just from the center. This allowed Jimena to explosively deepen over the next two days—over a 48-hour period, its winds increased by . At 06:00 UTC on August 29, Jimena reached its peak intensity as a strong Category 4 hurricane, possessing winds of and a minimum barometric pressure of 932 mbar (hPa; ). Soon after, Jimena turned to the west-northwest and underwent an eyewall replacement cycle.
Despite weakening slightly, Jimena remained at Category 4 status, thus becoming one of three simultaneous Category 4 Pacific hurricanes east of the International Date Line on August 30—the first such occurrence of its kind.
On August 30, Jimena completed the eyewall replacement cycle and quickly regained winds, this time with a larger eye of 40–45 mi (65–75 km) diameter. However, upwelling of cooler waters beneath the hurricane and entrainment of mid-level dry air into the circulation, as well as a second eyewall replacement cycle, resulted in a steady weakening beginning late on August 31. The next day, Jimena crossed 140°W as a Category 3 hurricane and entered the jurisdiction of the CPHC. Jimena continued to weaken slowly amid cooling sea surface temperatures and increasing westerly wind shear, eventually degrading below hurricane status on September 5.
Curving to the northwest, bursts of convection maintained Jimena as a tropical storm, in spite of westerly wind shear in excess of causing the low-level circulation center to be exposed. Eventually, on September 9, Jimena weakened to a tropical depression as it turned west-southwestwards towards the Hawaiian islands. Succumbing to the strong shear, Jimena degenerated into a remnant low just before 00:00 UTC on September 10, roughly north of the Hawaiian islands.
While passing north of the Hawaiian Islands on September 11, the remnants of Jimena diverted the winds to blow from the southeast, bringing humid air and
atmospheric instability
Atmospheric instability is a condition where the Earth's atmosphere is generally considered to be unstable and as a result the weather is subjected to a high degree of variability through distance and time. Atmospheric stability is a measure of th ...
to the east-facing slopes of the
Koʻolau Range
Koolau Range is a name given to the dormant fragmented remnant of the eastern or windward shield volcano of the Hawaiian island of Oahu. It was designated a National Natural Landmark in 1972.
Geology
It is not a mountain range in the normal ...
on
Oahu
Oahu () (Hawaiian language, Hawaiian: ''Oʻahu'' ()), also known as "The Gathering place#Island of Oʻahu as The Gathering Place, Gathering Place", is the third-largest of the Hawaiian Islands. It is home to roughly one million people—over t ...
. This generated prolonged heavy rains that led to localized flash floods, made worse by saturated soils from earlier rainfall events. Flood advisories were issued early on September 11 and were cancelled the next morning. Flooding from the Waikane Stream forced the
Kamehameha Highway
Kamehameha Highway is one of the main highways serving suburban and rural O‘ahu in the U.S. state of Hawai‘i. Informally known as Kam Highway, it begins at Nimitz Highway near Pearl Harbor and Hickam Air Force Base in Honolulu, serves the is ...
to close for a few hours, reopening only in the evening. A peak rainfall total on Oahu of was recorded at
Moanalua
Moanalua is a valley, a stream, an ahupuaa, and a residential neighborhood in Honolulu, Hawaii. The valley extends inland from behind Āliapaakai crater (Salt Lake) to the crest of the Koʻolau Range.
Neighboring areas include Māpunapuna and S ...
.
Tropical Storm Kevin
A tropical wave crossed Central America on August 25. Although it initially only produced transient bursts of convection, slow organization of the feature led to the formation of a tropical depression by 18:00 UTC on August 31 while located well south of Baja California. Steered northwest and the north-northwest, the cyclone intensified into Tropical Storm Kevin by 18:00 UTC the next day while being plagued by moderate wind shear. After reaching peak intensity with winds of and a pressure of 998 mbar (hPa; 29.47 inHg) on September 3, a further increase in upper-level winds caused the low- and mid-level circulations to become displaced. Devoid of deep convection, Kevin degenerated to a remnant low by 12:00 UTC on September 5; the remnant circulation drifted northwest and dissipated the following day.
Hurricane Linda
Early in September, a cluster of clouds began to organize, becoming Tropical Depression Fifteen-E at 18:00 UTC on September 5. The next day, the depression organized enough to be classified as a tropical storm and was given the name Linda. The nascent system rapidly strengthened as it moved on a northwestward course, with large amounts of deep convection forming around the center. Just 12 hours after becoming a tropical storm, Linda reached hurricane status, and on September 7, the system became a Category 2 hurricane. Linda's strengthening stalled thereafter as wind shear increased slightly and dry air intruded on Linda's inner core. The next day, however, Linda again quickly intensified, this time to a strong Category 3 hurricane with winds of and a minimum pressure of 950 mbar (hPa; ). From September 9 onward, Linda rapidly weakened as it moved into an area of dry, stable air and decreasing water temperatures, becoming a remnant low less than a week after forming. Linda's remnants slowed as they turned to the west-northwest and then back to the east before dissipating on September 14.
Copious amounts of water vapor pulled north from Linda brought thunderstorms to portions of California beginning September 10. Flooding and rock slides prompted numerous road closures. One person drowned in the
San Bernardino National Forest
The San Bernardino National Forest is a United States National Forest in Southern California encompassing of which are federal. The forest is made up of two main divisions, the eastern portion of the San Gabriel Mountains and the San Bernard ...
. Remnant moisture from Linda with a weak cold front also caused record heavy rainfall in Los Angeles on September 15, with three swift water rescues and roughly of rain across the Los Angeles Basin. Losses in the state reached $2.1 million. Moisture from Linda also catalyzed the formation of scattered thunderstorms across Utah on September 14, giving rise to two major flash flood incidents that became the deadliest flood event in Utah's history, with 21 people killed.
The first flash flood, occurring near
Hildale, swept away two vehicles carrying a total of 16 people while they were watching the rising floodwaters, killing 13 of them. Another death occurred when a man was swept away by floodwaters while traversing remote dirt roads. The second flash flood occurred in Keyhole Canyon at
Zion National Park
Zion National Park is an American national park located in southwestern Utah near the town of Springdale. Located at the junction of the Colorado Plateau, Great Basin, and Mojave Desert regions, the park has a unique geography and a variety ...
, causing seven
canyoneers within the area to perish. Damage totals in
Washington County, Utah
Washington County is a county in the southwestern corner of Utah, United States. As of the 2020 United States Census, the population was 180,279, making it the fifth-most populous county in Utah. Its county seat and largest city is St. Georg ...
reached $750,000, while downstream flooding caused a further $500,000 of damage in
Colorado City, Arizona
Colorado City is a town in Mohave County, Arizona, United States, and is located in a region known as the Arizona Strip. As of the 2020 census, the population of the town was 2,478, down from 4,821 in 2010. At least three Mormon fundamentalis ...
. The thunderstorms also caused some scattered damage across Arizona, with losses reaching $206,000.
According to
San Jose State University
San José State University (San Jose State or SJSU) is a public university in San Jose, California. Established in 1857, SJSU is the oldest public university on the West Coast and the founding campus of the California State University (CSU) sys ...
, Linda's remnants might have contributed to the severity of the
Valley Fire
The Valley Fire was a wildfire during the 2015 California wildfire season that started on September 12 in Lake County, California. It began shortly after 1:00 pm near Cobb with multiple reports of a small brush fire near the intersection of ...
.
Tropical Storm Malia
A trough formed near the eastern reaches of the Central Pacific on September 9. It moved swiftly westward and slowly organized into a tropical depression around 18:00 UTC on September 18 as deep convection formed near its center. The nascent cyclone moved northeast after formation, steered between a ridge to its northeast and a trough to its northwest. Strong upper-level winds plagued the system throughout its duration, but the depression nonetheless intensified into Tropical Storm Malia around 00:00 UTC on September 21 and attained peak intensity with winds of and a pressure of 992 mbar (hPa; 29.29 inHg) twelve hours later. Malia turned northwest under increasing influence from the upper-trough, which simultaneously increased wind shear over the cyclone. After lacking deep convection for several hours, the storm degenerated to a remnant low by 18:00 UTC on September 22. The post-tropical cyclone moved north before being absorbed by an extratropical low over the north-central Pacific the next day.
Tropical Depression Sixteen-E
A tropical wave gained enough organization to be declared Tropical Depression Sixteen-E on September 20. Located in an environment of strong southerly shear, the depression failed to intensify into a tropical storm. The next day, the heavily sheared system made landfall on Baja California, then on
Isla Tiburon, and finally in
Sonora, Mexico
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Federal Entities of Mexico. The state is divided into 72 municipalities; the ...
. It dissipated just hours later, with its remnants going on to affect parts of Arizona and New Mexico.
Widespread heavy rains in Baja California and Sonora caused heavy flooding. Preliminary damage estimates in
El Fuerte, Sinaloa
El Fuerte () is a city and El Fuerte Municipality its surrounding municipality in the northwestern Mexican state of Sinaloa. The city population reported in the 2010 census was 12,566 people.
El Fuerte, meaning "The Fort", was named a Pueblo M ...
, reached 300 million pesos (US$17.7 million).
The remnant low brought considerable moisture to the Desert Southwest, and later combined with other systems to produce flooding across the
Great Plains
The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...
and
Upper Midwest
The Upper Midwest is a region in the northern portion of the U.S. Census Bureau's Midwestern United States. It is largely a sub-region of the Midwest. Although the exact boundaries are not uniformly agreed-upon, the region is defined as referring ...
.
In Arizona, severe thunderstorms occurred in
Graham
Graham and Graeme may refer to:
People
* Graham (given name), an English-language given name
* Graham (surname), an English-language surname
* Graeme (surname), an English-language surname
* Graham (musician) (born 1979), Burmese singer
* Clan G ...
and
Pima
Pima or PIMA may refer to:
People
* Pima people, the Akimel O'odham, Indigenous peoples in Arizona (U.S.) and Sonora (Mexico)
Places
* Pima, Arizona, a town in Graham County
* Pima County, Arizona
* Pima Canyon, in the Santa Catalina Mountains ...
counties, resulting in $7,000 in property damage. Rainfall near
Safford totaled up to , while hail and winds gusting to were recorded at
Davis–Monthan Air Force Base
Davis–Monthan Air Force Base (DM AFB) is a United States Air Force base southeast of downtown Tucson, Arizona. It was established in 1925 as Davis–Monthan Landing Field. The host unit for Davis–Monthan AFB is the 355th Wing (355 WG) ass ...
. In addition, an EF0 tornado briefly touched down in adjacent
Cochise County
Cochise County () is a county in the southeastern corner of the U.S. state of Arizona. It is named after the Native American chief Cochise.
The population was 125,447 at the 2020 census. The county seat is Bisbee and the most populous city is ...
. Flash floods near
Quartzsite
Quartzsite is a town in La Paz County, Arizona, United States. According to the 2020 census, the population was 2,413.
Interstate 10 runs directly through Quartzsite which is at the intersection of U.S. Route 95 and Arizona State Route 95 wi ...
forced the closure of
Arizona State Route 95
State Route 95, also known as SR 95, is a north–south state highway along the western edge of Arizona that is split into two sections.
Route description
The southern segment begins in Quartzsite, Arizona, Quartzsite at its junction with U ...
and caused $5,000 in damage, while flooding in
Scottsdale caused $25,000 in damage. Meanwhile, in New Mexico, rainfall in
Roswell reached . One person drowned along the
Rio Grande
The Rio Grande ( and ), known in Mexico as the Río Bravo del Norte or simply the Río Bravo, is one of the principal rivers (along with the Colorado River) in the southwestern United States and in northern Mexico.
The length of the Rio G ...
in New Mexico. In
Albuquerque
Albuquerque ( ; ), ; kee, Arawageeki; tow, Vakêêke; zun, Alo:ke:k'ya; apj, Gołgéeki'yé. abbreviated ABQ, is the most populous city in the U.S. state of New Mexico. Its nicknames, The Duke City and Burque, both reference its founding in ...
, thunderstorms downed trees and flooded several streets. Property damage in New Mexico reached $85,000.
Tropical Storm Niala
On September 20, a tropical disturbance was identified southeast of Hawaii, moving westward south of the subtropical ridge. The disturbance slowly organized and became Tropical Depression Six-C on September 25. The system was upgraded into Tropical Storm Niala soon after as it headed west-northwest towards Hawaii, prompting the issuance of a tropical storm watch for the Big Island. Despite moving over very warm waters, a mid- to upper-level low-pressure system well northeast of the Hawaiian islands inflicted moderate wind shear over Niala, causing it to struggle to intensify. Eventually, at 18:00 UTC on September 26, Niala achieved peak intensity with winds of and a central pressure of 992 mbar (hPa; ). The detrimental effects of the wind shear soon began to show as Niala slowed and turned westwards away from Hawaii, with the low-level circulation becoming exposed as thunderstorms were sheared to the east. On September 28, Niala weakened to a tropical depression, and became a post-tropical low by September 29. The shallow remnant cyclone turned to the southwest under the influence of the low-level trade winds, dissipating by October 1.
Hurricane Marty
A tropical wave, the northern portion of which led to the formation of the Atlantic's
Tropical Depression Nine, emerged off the western coast of Africa on September 10. Steered steadily westward, the wave entered the East Pacific where deep convection coalesced around a well-defined center; this led to the formation of a tropical depression about southwest of Acapulco, Mexico by 18:00 UTC on September 26. The depression intensified into Tropical Storm Marty six hours later as it drifted north. Amid an environment conducive for strengthening, Marty reached hurricane intensity at 12:00 UTC on September 28 and attained peak intensity with winds of and a pressure of 987 mbar (hPa; 29.15 inHg) shortly thereafter. Wind shear abruptly increased following peak intensity, causing the cyclone to weaken quickly; it was downgraded to a tropical storm at 06:00 UTC on September 29 and degenerated into a remnant low a day later. The low eventually dissipated south of the Mexico coastline on October 4.
Heavy rains and flooding from the remnants of Marty rendered 35,000 people homeless in Sonora. Flooding in
Guaymas
Guaymas () is a city in Guaymas Municipality, in the southwest part of the state of Sonora, in northwestern Mexico. The city is south of the state capital of Hermosillo, and from the U.S. border. The municipality is located on the Gulf of Califo ...
damaged 800 homes and 400 vehicles; three people sustained injuries. Damage in the city reached 500 million pesos (US$30 million). Rains from Marty also caused several landslides in Guerrero, as well as flooding that damaged 300 homes west of Acapulco and injured two.
Hurricane Oho
In an uncommon occurrence characteristic of El Niño years, a slow-moving disturbance detached from a monsoon trough southeast of Hawaii and became Tropical Depression Seven-C on October 3. The system became Tropical Storm Oho shortly after as it tracked to the east-northeast. Under southwesterly wind shear, Oho failed to intensify over the next day or so while moving erratically, eventually settling on a generally northeastward path. On October 5, convection finally began to cover the low-level circulation center, allowing Oho to strengthen. Following further improvement of the storm's structure as seen on
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
and
microwave satellite imagery, the CPHC declared Oho a hurricane at 12:00 UTC on October 6. Accelerating northeastwards, Oho reached peak intensity as a strong Category 2 hurricane on October 7, with winds of and a minimum pressure of 957 mbar (hPa; ). Immediately after, the combination of southwesterly wind shear and cooler sea surface temperatures caused Oho to begin a weakening trend. Oho transitioned to an extratropical cyclone by 12:00 UTC on October 8 as its winds dropped below hurricane-force. The extratropical remnant of Oho later regained hurricane-force winds due to strong
baroclinicity
In fluid dynamics, the baroclinity (often called baroclinicity) of a stratified fluid is a measure of how misaligned the gradient of pressure is from the gradient of density in a fluid. In meteorology a baroclinic flow is one in which the densi ...
, before moving over Alaska in a weakened state on October 10 and dissipating a few hours later.
Tropical Depression Eight-C
On September 30, a tropical disturbance developed from a monsoon trough well east of the International Date Line. At that time, the system was about 1,035 mi (1,665 km) southwest of Hawaii. Slowly organizing over the next few days, the CPHC started to issue advisories on the system on October 3 and designated it as Tropical Depression Eight-C. Shortly after, however, increasing southerly wind shear prevented the storm from intensifying to a tropical storm and caused its convection to collapse. With the low-level circulation being displaced to the south of the quickly dissipating convection, the CPHC issued its final advisory on the next day. Eight-C's remnants slowly drifted west-northwestward, crossing the Date Line on October 6 and dissipating a few hours later.
The Japan Meteorological Agency, however, maintained the remnant system as
a tropical depression when it crossed the Date Line.
Tropical Storm Nora
A tropical wave departed the coast of Africa on September 19, eventually crossing Central America on October 3. It organized once in the Eastern Pacific, becoming a tropical depression around 12:00 UTC on October 9 and intensifying into Tropical Storm Nora 12 hours later. Moving along a west to west-northwest track, the cyclone entered the Central Pacific on October 11, where favorable environmental conditions allowed it to peak with winds of and a minimum pressure of 993 mbar (hPa; ), just shy of hurricane strength. Upper-level winds soon became hostile, causing the system to weaken to a tropical depression early on October 14, degenerate to a remnant low late the next day, and ultimately dissipate just southeast of Hawaii around 00:00 UTC on October 16.
The remnants of Nora brought heavy rains to the windward slopes of the Hawaiian Islands on October 16−17. Rainfall totals of caused minor flooding on the Big Island, Oahu, and
Maui
The island of Maui (; Hawaiian: ) is the second-largest of the islands of the state of Hawaii at 727.2 square miles (1,883 km2) and is the 17th largest island in the United States. Maui is the largest of Maui County's four islands, which ...
. On the Big Island, excessive
surface runoff
Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when th ...
briefly forced the closure of a portion of
Highway 19
Route 19, or Highway 19, may refer to:
For roads named "A19", see list of A19 roads.
International
* Asian Highway 19
* European route E19
* European route E019
Canada
* Alberta Highway 19
* British Columbia Highway 19
* Manitoba Highway 19
* ...
.
Hurricane Olaf
A broad low-pressure area formed well south of Mexico late on October 9. At first, it showed some signs of organization, but convection associated with the system soon diminished as it tracked steadily westwards. Eventually the system reorganized, and by October 15, it had gained enough organization to be designated as Tropical Depression Nineteen-E. The depression organized very slowly due to its elongated circulation, and only became a tropical storm two days later, upon which the NHC named it ''Olaf''. Soon after, Olaf began to rapidly intensify amid very favorable environmental conditions and became a hurricane on October 18, with hints of an eye starting to appear within a small central dense overcast.
Located at just 9.3°N, it broke the record for the lowest-latitude hurricane formation in the Eastern Pacific basin since reliable records began in 1971.
Olaf's intensification rate increased further overnight, and the next day, Olaf became a major hurricane with a well-defined pinhole eye.
At 9.8°N, it broke the record for the lowest-latitude major hurricane formation in the Eastern Pacific basin as well.
Six hours later, Olaf was upgraded to a Category 4 hurricane, the eighth of the season. Moving west-northwestwards, Olaf reached peak intensity with winds and a pressure of 938 mbar (hPa; ), just as it crossed into the Central Pacific basin.
After maintaining peak intensity for 12 hours, Olaf weakened to Category 3 status as it underwent an eyewall replacement cycle and encountered some dry mid-level air. Although the eye reappeared on satellite as the eyewall cycle completed, another one began while northwesterly wind shear increased, causing Olaf to weaken below major hurricane status while being pulled to the north by a passing trough. However, Olaf's northward movement resulted in a respite in shear, allowing Olaf to reintensify to a secondary peak intensity of on October 23. The next day, decreasing sea surface temperatures and another increase in wind shear finally began to weaken the storm for good. Despite maintaining a ragged eye until October 25, a further increase in wind shear from an approaching trough caused Olaf to weaken to a tropical storm while accelerating it to the east. On October 26, Olaf re-entered the Eastern Pacific, becoming the first storm on record to cross into the Central Pacific and turn back into the Eastern Pacific while still a tropical cyclone. The last of Olaf's deep convection continued to be sheared away, and the system became post-tropical on October 27 while still producing gale-force winds. Olaf's shallow remnants gradually weakened and turned back to the southwest, before dissipating on October 28.
Hurricane Patricia
Tropical Depression Twenty-E formed from a broad low-pressure area off the southwestern coast of Mexico on October 20. It only slowly intensified at first, becoming Tropical Storm Patricia later that day. Entering an atmosphere highly conducive to rapid deepening on October 21, Patricia organized rapidly, and became a hurricane late that day. On October 22, explosive intensification occurred, and in only 24 hours, Patricia became a Category 5 hurricane with winds.
The intensification rate rivaled those of
Hurricane Linda in
1997
File:1997 Events Collage.png, From left, clockwise: The movie set of ''Titanic'', the highest-grossing movie in history at the time; ''Harry Potter and the Philosopher's Stone'', is published; Comet Hale-Bopp passes by Earth and becomes one of t ...
and
Hurricane Wilma
Hurricane Wilma was an extremely intense and destructive Atlantic hurricane which was the most intense storm of its kind and the second-most intense tropical cyclone recorded in the Western Hemisphere, after Hurricane Patricia in 2015. Part ...
in
2005
File:2005 Events Collage V2.png, From top left, clockwise: Hurricane Katrina in the Gulf of Mexico; the Funeral of Pope John Paul II is held in Vatican City; "Me at the zoo", the first video ever to be uploaded to YouTube; Eris was discovered in ...
. Patricia subsequently attained winds of and a central pressure of 872 mbar (hPa; ), becoming the strongest tropical cyclone ever recorded in the Western Hemisphere, surpassing both the previous central pressure record set by
Hurricane Wilma
Hurricane Wilma was an extremely intense and destructive Atlantic hurricane which was the most intense storm of its kind and the second-most intense tropical cyclone recorded in the Western Hemisphere, after Hurricane Patricia in 2015. Part ...
and the previous 1-minute sustained wind record set by
Hurricane Allen
Hurricane Allen was a rare and extremely powerful Cape Verde hurricane that affected the Caribbean, eastern and northern Mexico, and southern Texas in August 1980. The first named storm and second tropical cyclone of the 1980 Atlantic hurrican ...
. Afterwards, as it approached and later passed over Western Mexico, Patricia weakened even more rapidly than it intensified; just 30 hours after peaking in intensity, it was downgraded to a remnant low at 18:00 UTC on October 24. However, Patricia's landfall near Cuixmala, Jalisco as a Category 4 hurricane with winds of , was still sufficient to qualify as the strongest landfall by any Pacific hurricane.
The precursor disturbance to Patricia brought heavy rain to Central America and parts of Mexico from October 18–20.
Approximately 223,000 people were affected by flooding and six were killed: four in
El Salvador
El Salvador (; , meaning " The Saviour"), officially the Republic of El Salvador ( es, República de El Salvador), is a country in Central America. It is bordered on the northeast by Honduras, on the northwest by Guatemala, and on the south b ...
, one in
Guatemala
Guatemala ( ; ), officially the Republic of Guatemala ( es, República de Guatemala, links=no), is a country in Central America. It is bordered to the north and west by Mexico; to the northeast by Belize and the Caribbean; to the east by H ...
, and one in
Nicaragua
Nicaragua (; ), officially the Republic of Nicaragua (), is the largest country in Central America, bordered by Honduras to the north, the Caribbean to the east, Costa Rica to the south, and the Pacific Ocean to the west. Managua is the cou ...
. Damage in
Chetumal
Chetumal (, , ; yua, label=Yucatec Maya, Chactemàal , ) is a city on the east coast of the Yucatán Peninsula in Mexico. It is the capital of the state of Quintana Roo and the municipal seat of the Municipality of Othón P. Blanco. In 2020 i ...
, Mexico reached 1.4 billion pesos (US$85.3 million). As a tropical cyclone, Patricia caused severe impacts when it made landfall in Jalisco, Mexico, killing six and causing at least 5.4 billion pesos (US$325 million) in damage.
An additional fatality occurred during evacuations in Jalisco. In Emiliano Zapata and
Chamela
Chamela is a small town in the state of Jalisco, on the west coast of Mexico. The town of Chamela sits on the south end of a bay called the ''Bahía de Chamela,'' or "Chamela Bay", on Federal Highway 200. San Mateo and Punta Pérula are the two ...
, the villages most badly affected by Patricia, violent winds tore off roofs, toppled concrete power poles and transmission lines, and defoliated trees. Hillsides were left barren and most small structures were severely damaged or completely destroyed.
Mexico's agricultural sector also suffered, with 42,000
ha (100,000
ac) of crops affected by Patricia, of which 15,000 ha (37,000 ac) were deemed a total loss. The papaya, banana, and plantain crops took the most damage.
The low death toll despite Patricia's landfall intensity was credited to the hurricane's small size, the low population density of the landfall area, as well as effective evacuations. The remnants of Patricia's upper-level circulation later produced rains in
South Texas
South Texas is a region of the U.S. state of Texas that lies roughly south of—and includes—San Antonio. The southern and western boundary is the Rio Grande, and to the east it is the Gulf of Mexico. The population of this region is about 4.96 ...
, causing flash floods that left $52.5 million in damage.
Tropical Storm Rick
A tropical wave moved off the western coast of Africa on November 3, entering the East Pacific roughly two weeks later. The disturbance encountered a persistent area of convection in the Intertropical Convergence Zone, eventually coalescing into a tropical depression by 12:00 UTC on November 18 while located 715 mi (1,150 km) south-southeast of the southern tip of Baja California. Plagued by moderate southeasterly wind shear, the depression slowly intensified into Tropical Storm Rick and simultaneously attained peak intensity with winds of and a pressure of 1002 mbar (hPa; 29.59 inHg) by 12:00 UTC on November 19. The cyclone failed to intensify further as it tracked west-northwest within a dry environment, weakening to a tropical depression by 06:00 UTC on November 22 and further degenerating into a remnant low 12 hours later. The low tracked northwest and eventually southwest prior to dissipating early on November 26.
Hurricane Sandra
A tropical wave that emerged off the west coast of Africa on November 6 entered the Eastern Pacific on November 21. The system organized and was classified as a tropical depression on November 23 well south of Mexico. Environmental conditions, including high sea surface temperatures and low wind shear, were highly conducive to intensification and the storm quickly organized, becoming Tropical Storm Sandra early on November 25. A small central dense overcast developed atop the storm and Sandra reached hurricane status early on November 25 after the consolidation of an eye. The hurricane achieved its peak as a Category 4 hurricane with winds of and a pressure of 934 mbar (hPa; ) early on November 26. This made Sandra the strongest November hurricane on record in the Northeastern Pacific, surpassing
Hurricane Kenneth The name Kenneth has been used for four tropical cyclones in the Eastern Pacific Ocean and one in the South-West Indian Ocean.
In the Eastern Pacific:
* Hurricane Kenneth (1993) – Category 4 hurricane that did not affect land.
* Hurricane Ke ...
in 2011. Thereafter, increasing shear degraded the hurricane's structure and weakening ensued. Rapid weakening took place on November 27 and Sandra's circulation became devoid of convection as it diminished to a tropical storm that evening. The cyclone degenerated into a remnant low soon thereafter and ultimately dissipated just off the coast of Sinaloa, Mexico, on November 29.
As the precursor to Sandra traversed Central America, it produced unseasonably heavy rainfall that triggered flooding and landslides. Four people died in various incidents related to the system: three in El Salvador and one in
Honduras
Honduras, officially the Republic of Honduras, is a country in Central America. The republic of Honduras is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Oce ...
. Initially expecting a landfalling storm, officials in Northwestern Mexico prepared equipment for power outages, closed schools, and evacuated 180 residents. Sandra's effects largely consisted of light to moderate rainfall; some traffic accidents and landslides resulted from this, though the overall impacts were limited.
Tropical Depression Nine-C
Despite the official end of the hurricane season about a month prior, a
westerly wind burst
A westerly wind burst is a phenomenon commonly associated with El Niño events, whereby the typical east-to-west trade winds across the equatorial Pacific shift to west-to-east. A westerly wind burst is defined by Harrison and Vecchi (1997) as sus ...
in the equatorial waters of the Central Pacific led to the development of a tropical disturbance on December 27.
This feature also led to the formation of
Cyclone Ula
Severe Tropical Cyclone Ula was a powerful and long-lived tropical cyclone during late December 2015 and mid-January 2016. It originated from a tropical disturbance on December 26, 2015, east of the Solomon Islands. Moving generally east, dev ...
in the
South Pacific.
Moving slowly eastward, the disturbance stayed in an environment with anomalously high sea surface temperatures and ample ocean heat content associated with the ongoing El Niño event, allowing thunderstorms in the system to develop and persist. Turning northwards, the system formed a closed low-level circulation and continued to slowly organize. At 00:00 UTC on December 31, Tropical Depression Nine-C formed at a very low latitude of 2.2°N. Moving slowly westwards, Nine-C never reached tropical storm strength due to its proximity to the equator and the presence of 20-knot vertical wind shear over the system, leaving the 2015 season one storm shy of the record from 1992. As convection in and around the depression was rapidly sheared to the west, the depression was unable to support itself and was downgraded into a remnant low at 00:00 UTC on January 1, 2016, marking the latest end to a Pacific hurricane season on record. The remnant low dissipated later that day.
Storm names
The following names were used to name storms that formed in the Eastern Pacific Ocean within the
National Hurricane Center
The National Hurricane Center (NHC) is the division of the United States' NOAA/National Weather Service responsible for tracking and predicting tropical weather systems between the Prime Meridian and the 140th meridian west poleward to the 3 ...
's area of responsibility during 2015.
This is the same list used in the
2009 season.
For storms that form in the
Central Pacific Hurricane Center
The Central Pacific Hurricane Center (CPHC) of the United States National Weather Service is the official body responsible for tracking and issuing tropical cyclone warnings, watches, advisories, discussions, and statements for the Central Pacifi ...
's area of responsibility, encompassing the area between
140°W and the
International Date Line
The International Date Line (IDL) is an internationally accepted demarcation on the surface of Earth, running between the South and North Poles and serving as the boundary between one calendar day and the next. It passes through the Pacific O ...
, all names are used in a series of
four rotating lists.
The next nine names that were slated for use are shown below. Eight of these names were used throughout the course of the season. This season saw more named storms that formed in the Central Pacific basin than any other season on record.
Operationally, Kilo was thought to have formed on August 20, and hence received a name before Loke, which formed on August 21. Kilo's date of formation was shifted to August 22 after post-storm analysis.
Retirement
On April 25, 2016, at the 38th session of the RA IV Hurricane Committee, the
World Meteorological Organization
The World Meteorological Organization (WMO) is a specialized agency of the United Nations responsible for promoting international cooperation on atmospheric science, climatology, hydrology and geophysics.
The WMO originated from the Internati ...
retired the name ''Patricia'' due to its extreme intensity, and it will not be used again for another
Pacific hurricane
A Pacific hurricane is a mature tropical cyclone that develops within the northeastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regio ...
. It was replaced with ''Pamela'' for the
2021 Pacific hurricane season
The 2021 Pacific hurricane season was a moderately active Pacific hurricane season, with above-average tropical activity in terms of named storms; but featured below-average activity in terms of major hurricanes and a near-normal accumulated cycl ...
.
Season effects
This is a table of all the storms that have formed in the 2015 Pacific hurricane season. It includes their duration, names, areas affected, damages, and death totals. Deaths in parentheses are additional and indirect (an example of an indirect death would be a traffic accident), but were still related to that storm. Damage and deaths include totals while the storm was extratropical, a wave, or a low, and all the damage figures are in 2015 USD.
See also
*
Tropical cyclones in 2015
During 2015, tropical cyclones formed in seven major bodies of water, commonly known as tropical cyclone basins. Tropical cyclones will be assigned names by various weather agencies if they attain maximum sustained winds of . During the year, on ...
*
List of Pacific hurricanes
This is a list of notable Pacific hurricanes, subdivided by reason for notability. Notability means that it has met some criterion or achieved some statistic, or is part of a top ten for some superlative. It includes lists and rankings of Pacific ...
*
Pacific hurricane season
A Pacific hurricane is a mature tropical cyclone that develops within the northeastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regio ...
*
2015 Atlantic hurricane season
The 2015 Atlantic hurricane season was the last of three consecutive below average Atlantic hurricane seasons. It produced twelve tropical cyclones, eleven named storms, four hurricanes, and two major hurricanes. The Accumulated Cyclone Energy ( ...
*
2015 Pacific typhoon season
The 2015 Pacific typhoon season was a slightly above average season that produced 27 tropical storms, 18 typhoons, and nine super typhoons. The season ran throughout 2015, though most tropical cyclones typically develop between May and November. ...
*
2015 North Indian Ocean cyclone season
* South-West Indian Ocean cyclone seasons:
2014–15,
2015–16
* Australian region cyclone seasons:
2014–15,
2015–16
* South Pacific cyclone seasons:
2014–15,
2015–16
*
South Atlantic tropical cyclone
South Atlantic tropical cyclones are unusual weather events that occur in the Southern Hemisphere. Strong wind shear, which disrupts the formation of cyclones, as well as a lack of weather disturbances favorable for development in the South Atl ...
Notes
References
External links
National Hurricane Center WebsiteNational Hurricane Center's Eastern Pacific Tropical Weather OutlookCentral Pacific Hurricane Center WebsiteServicio Meteorológico Nacional WebsiteNHC 2015 Pacific hurricane season archive
{{Tropical cyclone season, 2015
Pacific hurricane seasons
2015 Epac