The 2021 Pacific hurricane season was a moderately active
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 ...
season, with above-average tropical activity in terms of
named storm
Tropical cyclones and subtropical cyclones are named by various warning centers to simplify communication between forecasters and the general public regarding forecasts, watches and warnings. The names are intended to reduce confusion in the ...
s; but featured below-average activity in terms of major hurricanes and a near-normal
accumulated cyclone energy (ACE). Five of the season's nineteen named storms 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 ...
in
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, the most since
2018
File:2018 Events Collage.png, From top left, clockwise: The 2018 Winter Olympics opening ceremony in PyeongChang, South Korea; Protests erupt following the Assassination of Jamal Khashoggi; March for Our Lives protests take place across the Unit ...
. The season officially began on May 15 in the Eastern Pacific, and on June 1 in the Central Pacific; both ending on November 30. These dates historically describe the period each year when most tropical cyclones
form
Form is the shape, visual appearance, or configuration of an object. In a wider sense, the form is the way something happens.
Form also refers to:
*Form (document), a document (printed or electronic) with spaces in which to write or enter data
...
in the Pacific basin and are adopted by convention. However, the formation of tropical cyclones is possible at any time of the year, as illustrated by the formation of Tropical Storm Andres on May 9, which became the earliest forming tropical storm in the northeastern Pacific proper (east of 140°W longitude) on record.
In June,
Tropical Storm Dolores The name Dolores (or Delores, a misspelling) has been used for twelve tropical cyclones in the Eastern Pacific Ocean and for one in the Western Pacific.
In the Eastern Pacific:
* Hurricane Dolores (1966) – Category 1 hurricane that stayed out at ...
made landfall near the border of the Mexican states of
Colima
Colima (), officially the Free and Sovereign State of Colima ( es, Estado Libre y Soberano de Colima), is one of the 31 states that make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima.
Colima i ...
and
Michoacán, killing three people and resulting in US$50 million in insured losses. Just a week later,
Hurricane Enrique paralleled the west coast of Mexico, causing an additional two fatalities and a similar amount of damage. In August,
Hurricane Nora made landfall on the state of
Jalisco and paralleled the Pacific coast of Mexico until dissipating, resulting in an estimated $100 million in damage and three more deaths. Less than two weeks later,
Hurricane Olaf made landfall on
Baja California Sur as a Category 2 hurricane. In October,
Hurricane Pamela
Hurricane Pamela was a Category 1 Pacific hurricane that caused seven deaths and US$10 million in damage across the northwestern and western states of Mexico in October 2021. The sixteenth named storm and seventh hurricane of the 2021 Pacific hu ...
struck
Nayarit
Nayarit (), officially the Free and Sovereign State of Nayarit ( es, Estado Libre y Soberano de Nayarit), is one of the 31 states that, along with Mexico City, comprise the Federal Entities of Mexico. It is divided in 20 municipalities and its ...
at Category 1 intensity, leaving four people missing and severe flooding. Later that month,
Hurricane Rick struck near the
Michoacán-
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 ...
border at peak intensity as a strong Category 2 hurricane.
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Seasonal forecasts
Forecasts include weekly and monthly changes in important factors that help determine the number of tropical storms, hurricanes, and major hurricanes within a particular year. According to 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 ...
(NOAA), the average hurricane season in the
Eastern and Central Pacific between 1991 and 2020 contained approximately 15 tropical storms, 8 hurricanes, and 4 major hurricanes. The
NOAA generally classifies a season as above average, average, or below average based on the cumulative ACE index, but occasionally the number of tropical storms, hurricanes, and major hurricanes within a hurricane season is also considered. Factors they expected to reduce activity were near- or below-average
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 mas ...
s across the eastern Pacific and the
El Niño–Southern Oscillation
El Niño–Southern Oscillation (ENSO) is an irregular periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting the climate of much of the tropics and subtropics. The warming phase of the sea te ...
remaining in the neutral phase, with the possibility of a
La Niña
La Niña (; ) is an oceanic and atmospheric phenomenon that is the colder counterpart of as part of the broader El Niño–Southern Oscillation (ENSO) climate pattern. The name ''La Niña'' originates from Spanish for "the girl", by an ...
developing.
On May 12, 2021, the
Servicio Meteorológico Nacional issued its forecast for the season, predicting a total of 14–20 named storms, 7–10 hurricanes, and 4–5 major hurricanes to develop.
On May 20, 2021, 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 ...
(NOAA) issued their outlook, calling for a below-normal to near-normal season with 12–18 named storms, 5–10 hurricanes, 2–5 major hurricanes, and an
accumulated cyclone energy index of 65% to 120% of the median.
Seasonal summary
![Nine-E, Hilda and Ignacio - Aug 2, 2021](https://upload.wikimedia.org/wikipedia/commons/8/83/Nine-E%2C_Hilda_and_Ignacio_-_Aug_2%2C_2021.jpg)
The 2021 Pacific hurricane season began on May 15 in the East Pacific and on June 1 in the Central Pacific.
Overall activity included 19 named storms, 8 hurricanes, and 2 major hurricanes. The total of named storms was above the 1991–2020 average, while the number of hurricanes was average, and the sum of major hurricanes was below average.
The official start date was preceded by the formation of Tropical Storm Andres, the earliest named storm on record in the East Pacific.
It was accompanied by Tropical Storm Blanca later in May. The following month included the formations of tropical storms Carlos and Dolores, in addition to Hurricane Enrique. While Carlos remained away from land, Dolores made landfall on the Mexico coastline and Enrique delivered impacts across southwestern sections of the country while it passed just offshore. Above-average seasonal activity continued into July with the development of hurricanes Felicia and Hilda, Tropical Storm Guillermo, and Tropical Depression Nine-E; none of these cyclones impacted land. In August, Hurricane Nora made landfall along the west-central coastline of Mexico. Its formation was preceded by Hurricane Linda and tropical storms Ignacio, Kevin, and Marty, which did not impact land. September marked a stark turn around to the activity of the previous months, as it only featured Olaf, which struck
San José del Cabo
San José del Cabo (, ''Saint Joseph of the Cape'') is a city located in southern Baja California Sur state, Mexico. It is the seat of Los Cabos Municipality lying at a shallow bay northeast of Cabo San Lucas on the Gulf of California. The city ...
as a Category 2 hurricane. Two hurricanes – Pamela and Rick – moved ashore the Mexico coastline in October. An additional two storms, Terry and Sandra, developed in November, the fourth consecutive November with at least one named storm. Furthermore, those cyclones existed simultaneously, the first occurrence in the East Pacific during November on record. The Accumulated Cyclone Energy index for the 2021 Pacific hurricane season as calculated by Colorado State University using data from the National Hurricane Center was approximately 94 units, about 30 percent below average.
Systems
Tropical Storm Andres
In early May, the passage of a convectively-coupled
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 ...
(CCKW) enhanced the eastern Pacific monsoon trough, leading to an area of disturbed weather. This disturbance interacted with a Gulf of Tehuantepec gap wind event, which led to the formation of an ill-defined
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 ...
. Despite a marginal environment of wind shear and dry air, the system slowly organized and developed into a tropical depression around 06:00 UTC on May 9. Six hours later, it intensified into Tropical Storm Andres, becoming the earliest tropical storm on record in the East Pacific basin. Andres maintained peak winds of 40 mph (65 km/h) as it curved north-northwest, and the compounded effects of colder waters and drier air atop moderate wind shear instead caused the system to begin weakening. All associated convective activity dissipated by 06:00 UTC on May 11, when Andres was downgraded to a remnant area of low pressure. The low curved west on May 12 and dissipated later that day.
There are no reports of damage or casualties directly associated with Tropical Storm Andres; however, some other rainstorms associated with Andres produced heavy
rainfall
Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water f ...
in Southwestern Mexico.
Moisture from the storm caused intense rain and even a
hailstorm
Hail is a form of solid precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fal ...
as far east as the
State of Mexico, including in the state's capital,
Toluca
Toluca , officially Toluca de Lerdo , is the state capital of the State of Mexico as well as the seat of the Municipality of Toluca. With a population of 910,608 as of the 2020 census, Toluca is the fifth most populous city in Mexico. The city f ...
.
Vehicles became stranded in floods, some small trees got knocked over, and about 50 houses were damaged by a flooding river. Four municipalities in the
Toluca Valley
The Toluca Valley is a valley in central Mexico, just west of the Valley of Mexico (Mexico City), the old name was Matlatzinco. The valley runs north–south for about , surrounded by mountains, the most imposing of which is the Nevado de Toluca Vo ...
were flooded; 30 cars were stranded in a flooded parking lot of a church in
Metepec
Metepec () is a municipality in the State of Mexico in Mexico and is located directly to the east of the state capital, Toluca, at an altitude of above sea level. The center of Mexico City lies some 50 km further to the east. The city of ...
, and in
Lerma, a shopping center's roof was damaged due to flying debris and hail.
Tropical Storm Blanca
Blanca originated from a
tropical wave that crossed Central America on May 27. Shower and thunderstorm activity increased ahead of the wave axis, followed by the formation of a low-pressure area. After further organization, the developed into a tropical depression around 18:00 UTC on May 30. It intensified into Tropical Storm Blanca around 12:00 UTC the next day. Favorable environmental conditions allowed the cyclone to intensify, and it attained peak winds of 60 mph (95 km/h) on June 1 when prominent
rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands can be stratiform or convective, and are generated by differences in temperature. When noted on weather radar im ...
s wrapped into the center. Thereafter, an
upper-level trough off the southwestern United States increased shear over Blanca and injected dry air into the core, resulting in a weakening trend. The storm's low-level circulation became separated from convection, and it degenerated to a remnant low by 00:00 UTC on June 4. The remnants of Blanca, which were previously tracking west-northwest, curved toward the west before dissipating later the next day.
Tropical Storm Carlos
A trough developed within the
Intertropical Convergence Zone (ITCZ) on June 1. It moved west across the eastern Pacific for several days but failed to develop into a tropical cyclone on several occasions, either because it lacked a coherent circulation or because it lacked sustained convection. A burst of thunderstorms resulted in the formation of a well-defined center on June 12, and the system steadily organized over ensuing hours, finally resulting in the formation of a tropical depression by 12:00 UTC that day. Six hours later, the depression intensified into Tropical Storm Carlos to the southwest of Baja California Sur. The surrounding environment was initially favorable for development and allowed the system to reach peak winds of 50 mph (85 km/h) as it curves west-southwest. However, increasing dry air around the storm caused Carlos to gradually lose its convection, which ultimately resulted in its degradation to a remnant low by 12:00 UTC on June 16. The remnant system was reabsorbed into the ITCZ the following day.
Tropical Storm Dolores
A broad cyclonic gyre over Central America, spawned from the interaction of the monsoon trough and a tropical wave, led to the formation of an area of low pressure south of Mexico on June 16. The low gradually organized and became a tropical depression around 18:00 UTC on June 17 while located about south-southwest of Acapulco. The depression became Tropical Storm Dolores within six hours. Ridging over Mexico shifted east as Dolores developed, causing the cyclone to curve to the north-northwest. A favorable environment facilitated its development, and the storm reached peak winds of 70 mph (110 km/h) as it made landfall near San Juan de Alima, Michoacán, around 15:00 UTC on June 19. It harbored a well-defined eyewall at the time, and it is possible that Dolores temporarily surpassed tropical storm intensity. Once inland, though, the system quickly weakened over the high terrain of southwestern Mexico, dissipating around 06:00 UTC on June 20.
Dolores produced a wide expanse of or greater rainfall across southwestern Mexico, including a peak accumulation of in Callejones, Colima. At least 20 municipalities in Michoacán were affected by flooding or uprooted trees, blocking many routes through these communities. In Jalisco, the Marabasco River overflowed its banks, briefly isolating 80 homes. Throughout Guerrero, Michoacán, Colima, and Jalisco, more than 50,000 customers lost power. Overall damage to more than 1,000 structures totaled in excess of $50 million. Three people were killed by lightning, two in Oaxaca and one in Jalisco.
Hurricane Enrique
A tropical wave left Africa on June 14 and crossed Central America a week later. The system coalesced as it moved south of Mexico, becoming Tropical Storm Enrique by 12:00 UTC on June 25 since the incipient system was already producing
gale
A gale is a strong wind; the word is typically used as a descriptor in nautical contexts. The U.S. National Weather Service defines a gale as sustained surface winds moving at a speed of between 34 and 47 knots (, or ).[rapid intensification
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 wi ...]
. Enrique intensified into a hurricane around 12:00 UTC on June 26 and reached peak winds of 90 mph (150 km/h) the next morning as it was characterized by a cloud-filled eye. The storm curved north and then bent back northwest, passing within 45 miles (75 km) of the Mexico coastline. Dry air off the mountainous terrain of that country, and later colder waters, soon caused Enrique to lose organization. By 18:00 UTC on June 30, the increasingly disheveled circulation was absorbed into a broad trough east of Baja California.
Two people died from rip currents in
Pie de la Cuesta, Guerrero
Pie de la Cuesta is a small beach resort town in the Mexican state of Guerrero, approximately 5 miles north-west of Acapulco, and it is the location of a military base of the Mexican Air Force.
History
Cave paintings from 1.200 BC and petrog ...
. At least 207 homes were damaged by landslides and winds caused by Enrique in Guerrero. In
Lázaro Cárdenas, Michoacán
Lázaro Cárdenas () is a port city in Michoacán bordered to the east by Guerrero. Lázaro Cárdenas is located in the southern part of the Mexican state of Michoacán. It was formerly known as Los Llanitos, but changed its name as a tribute to L ...
, areas were inundated by more than 50 cm (19 in) of floodwater. A total of 115,904 customers lost power across
Jalisco, although 96% of homes returned with power a couple of hours later. A citywide power outage also occurred in
Tepic
Tepic () is the capital and largest city of the western Mexican state of Nayarit, as well as the seat of the Tepic Municipality.
Located in the central part of the state, it stands at an altitude of above sea level, on the banks of the Rí ...
.
Hurricane Felicia
A disturbance of unclear origin was identified over Central America and the far eastern Pacific on July 9. The system progressed westward over the open ocean during the following days, developing into a tropical depression around 00:00 UTC on July 14 and becoming Tropical Storm Felicia six hours later. Felicia immediately underwent rapid intensification, becoming a hurricane by 06:00 UTC on July 15 and a major hurricane 24 hours later. Early on July 17, the system attained peak winds of 145 mph (235 km/h).
At that time, Felicia displayed a warm eye encapsulated by a ring of convection and little additional rainbands outside the eyewall, a signature sign of an
annular tropical cyclone
An annular tropical cyclone is a tropical cyclone that features a normal to large, symmetric eye surrounded by a thick and uniform ring of intense convection, often having a relative lack of discrete rainbands, and bearing a symmetric appearance ...
. It was also a very small storm, with hurricane-force winds extending only 15 miles (25 km) from the center. After a brief westward turn, Felicia resumed a west-northwestward motion into much more hostile environmental conditions on July 18. The cyclone rapidly weakened and degenerated to a remnant low by 18:00 UTC on July 20 while located well east of Hawaii. Low-level wind flow steered the remnant low of Felicia to the west-southwest, and it opened into a trough two days later.
Tropical Storm Guillermo
A tropical wave moved off the coast of Africa on July 6 and emerged into the eastern Pacific basin a week later, where the background environment already favored cyclonic spin. Consequently, a disturbance spawned along the wave axis developed into a tropical depression by 00:00 UTC on July 17 and further into Tropical Storm Guillermo within twelve hours. A potent ridge pushed the cyclone west-northwest, while a favorable combination of low wind shear and very warm ocean temperatures allowed it to intensify. Guillermo reached peak winds of 60 mph (95 km/h) on July 18 despite a slightly less organized satellite appearance. Around this time, the storm produced tropical storm-force gusts on Socorro and Clarion islands. After its peak, Guillermo encountered cooler waters and higher wind shear, which ultimately caused it to degenerate to a remnant low by 00:00 UTC on July 20. The low moved faster to the west-southwest before it was absorbed by a trough a day later far away from land.
Hurricane Hilda
On July 24, a disturbance formed near south of
Gulf of Tehuantepec
Gulf of Tehuantepec () is a large body of water on the Pacific coast of the Isthmus of Tehuantepec, southeastern Mexico, at . Many (but not all) Pacific hurricanes form in or near this body of water. A strong, gale-force wind called the Tehu ...
, which was moving parallel offshore of southern Mexico. As it moved farther from the coast of Mexico, the disturbance gradually became organized, and on July 28, a low pressure area formed, as satellite imagery showed that the associated shower activity was showing signs of organization. The low-pressure area further organized, with a pair of ASCAT passes showing that the low-pressure area had strengthened significantly and was producing tropical storm-force winds, with the circulation looking well-defined on satellite imagery. On July 30, it was designated as a tropical storm. Hilda intensified to a high-end tropical storm a day later as a
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 ...
developed. Later, Hilda further intensified to a hurricane as a short-lived eye appeared in its central dense overcast. Hilda held a similar appearance the next day, with its center located north of its central dense overcast. Hilda briefly developed a closed mid-level eye the next day, though the low-level and mid-level centers were not stacked due to wind shear. However, it became less organized later that day, with a less distinct eye and an incomplete eyewall. By the next day, Hilda was downgraded to a high-end tropical storm since the eyewall was no longer well-defined, while convection continued to pulse in the southern semicircle. Deep convection continued to wane due to shear, cooler waters, and more stable air. By August 5, Hilda weakened into a tropical depression after a rapid weakening of convection near the center. However, convection resumed pulsing later. On August 6, at 03:00 UTC, Hilda became a post-tropical cyclone, as it became devoid of deep convection due to sub- sea-surface temperatures.
Tropical Storm Jimena
On July 26, the NHC noted a disturbance located about south-southwest of the southern tip of Baja California. The system moved parallel to another disturbance which later became Hurricane Hilda. By 21:00 UTC on July 30, the disturbance attained a well-defined center of circulation with sufficient organized convection and was classified as a tropical depression, bearing the designation ''Nine-E''. The depression was initially forecast to become a tropical storm, but failed to do so due to dry air and
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 horizont ...
caused by nearby Hurricane Hilda. Early on August 1, the system degenerated into a remnant low. Even though Nine-E was a tropical low, the NHC still monitored the system for further development On August 4, it re-intensified into a tropical depression again while maintaining two rainbands in a slightly elongated circulation. On the next day, at 09:00 UTC, the depression intensified into a tropical storm, with the NHC naming it as ''Jimena'', as the storm's deep convection had increased near the low-level center and based on satellite imagery, the storm was producing tropical storm force winds. The convection later diminished on August 6, as it moved over cooler sea-surface temperatures and encountering high wind shear and dry airmass. However, despite all this, Jimena managed its intensity, as it continued to produce tropical storm force winds, based on ASCAT data. A deep convective mass also continued to persist over the center of Jimena. At 21:00 UTC, the NHC issued its last advisory, downgrading the system to a tropical depression as it entered the CPHC's area of responsibility. Its deep convection weakened significantly as it moved over cool sea surface temperatures causing Jimena to weaken. The CPHC later issued its only bulletin for Jimena at 03:00 UTC the next day, stating that Jimena had become a post-tropical cyclone as its deep convection had collapsed completely.
Tropical Storm Ignacio
A parade of tropical waves entered the eastern Pacific in late July. By 12:00 UTC on August 1, one wave spawned a disturbance that had gained sufficient organization to be designated a tropical depression. Moderately wind shear inhibited the newly formed system, and though it intensified into Tropical Storm Ignacio a day later, the system failed to organize beyond that strength as its low-level circulation became separated from associated convective activity. Around this time, the system produced tropical storm-force gusts on Socorro Island. Later on August 2, Ignacio began to succumb to increasingly dry air and cooler waters. It degenerated to a remnant low around 00:00 UTC on August 4, which moved erratically until it dissipated southwest of Baja California twelve hours later.
Tropical Storm Kevin
A tropical wave entered the eastern Pacific on August 1, and the resultant disturbance organized into a tropical depression around 12:00 UTC on August 7. The newly formed cyclone swiftly intensified amid very high mid-level moisture and ocean temperatures, becoming Tropical Storm Kevin six hours later and reaching peak winds of 65 mph (100 km/h) on August 8. Wind shear abruptly increased later that day, confining the storm's convection into the western semicircle. Kevin passed near Clarion Island on August 10 as it moved west then west-northwest, producing tropical storm-force gusts there. By 12:00 UTC on August 12, all associated convection dissipated, and the system degenerated to a remnant low. The low curved northwest and dissipated west of Baja California Sur on August 15.
Hurricane Linda
A tropical wave moved into the eastern Pacific on August 6, spawning an area of disturbed weather that subsequently became a tropical depression around 06:00 UTC on August 10. It moved generally westward, intensifying into Tropical Storm Linda six hours later and organizing further beyond that point, but temporarily succumbing to some dry air and wind shear. As those factors subsided, Linda strengthened into a hurricane on August 12 and soon began rapidly intensifying over warm ocean waters, a process that culminated in it becoming the season's second and final major hurricane by 18:00 UTC on August 13. The next day, Linda peaked as a Category 4 cyclone with winds of 130 mph (215 km/h). Between August 14–15, the storm underwent 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 ...
. Much like Hurricane Felicia, Linda soon acquired characteristics of an annular hurricane, with a 45 mi (75 km) wide eye surrounded by deep, symmetric convection and little additional banding. The hurricane fluctuated in intensity over the next few days as it moved over varying ocean temperatures and through drier air. Late on August 18, Linda progressed over ocean waters cooler than , which led to rapid weakening. The system ultimately degenerated to a gale-force remnant low by 18:00 UTC on August 19. It later crossed into the Central Pacific basin.
The remnants of the storm later dropped heavy rains from August 22 to August 24 across
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 state ...
, with falling along the western slopes.
Tropical Storm Marty
The Atlantic's
Hurricane Grace struck mainland Mexico as a Category 3 hurricane on August 21. Although that storm's low-level center dissipated over the mountainous terrain of Mexico, its mid-level circulation emerged into the eastern Pacific and soon became encompassed by deep convection. That thunderstorm activity spawned a new surface center separate from Grace's previous one, and further organization of the disturbance led to the formation of Tropical Storm Marty by 00:00 UTC on August 23. The newly christened tropical storm reached peak winds of 45 mph (75 km/h) early on August 23, but it began to weaken shortly thereafter as wind shear increased. Marty moved west as it encountered an increasingly hostile environment of dry air and cooler waters, resulting its degeneration to a remnant low by 06:00 UTC on August 24. Three days later, it dissipated into a trough well to the west-southwest of Baja California Sur.
Hurricane Nora
On August 19, an area of disturbed weather formed west of the southern Mexico coast, which was producing disorganized thunder storms. A day later, the system became better defined and signs of the organization of showers and thunderclouds were also noted. On August 25, at 11:00 UTC the system developed a well-defined circulation as a scatterometer pass showed that it was producing near tropical storm-force winds. Thus, the NHC designated the system as ''Tropical Depression Fourteen-E''. A day later at 17:00 UTC, Fourteen-E intensified into a tropical storm, with the NHC naming it as ''Nora'' as its deep convection had organized significantly along with improved curvature of its bands. On August 28, at 11:00 UTC, Nora intensified into a Category 1 hurricane, as its inner core structure became further defined with the formation of a low-level eyewall. Nora made landfall on
Jalisco, after which it skirted the coasts of
Nayarit
Nayarit (), officially the Free and Sovereign State of Nayarit ( es, Estado Libre y Soberano de Nayarit), is one of the 31 states that, along with Mexico City, comprise the Federal Entities of Mexico. It is divided in 20 municipalities and its ...
and
Sinaloa as a weakening storm and rapidly dissipated on August 30 as it moved further inland. It brought considerable damage to Mexico, killing two people and leaving six missing due to a landslide in
Cabo Corrientes.
It had also caused flooding and mudslides. The damage caused by the passage through Nora to the country reached 200 million pesos (US$10 million). Nora's remnants caused heavy rain in
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
,
Colorado
Colorado (, other variants) is a state in the Mountain states, 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 wes ...
, and
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 ...
.
Hurricane Olaf
A tropical wave moved off Africa on August 22. It fractured twice over subsequent days, with portions of the original wave axis spawning tropical storms Kate and Mindy in the Atlantic. The southern piece of the wave continued into the East Pacific on September 2, where it led to the formation of a new tropical depression around 18:00 UTC on September 7 about west-southwest of Manzanillo, Colima. The system drifted toward the northwest in weak steering currents, while favorable environmental parameters allowed it to intensify. The depression became Tropical Storm Olaf around 12:00 UTC on September 8, and Olaf became a hurricane 24 hours later. The cyclone's eye and overall presentation continued to improve into September 10, and Olaf reached its peak as a Category 2 hurricane with winds of 105 mph (165 km/h) at 02:50 UTC that day. It concurrently made landfall near San Jose del Cabo, Baja California Sur. The storm only slowly weakened over land, but this process accelerated as it continued into stable air offshore. It curved west and degenerated to a remnant low around 06:00 UTC on September 11. The low continued in that direction for another day before dissipating.
As Olaf paralleled the Mexico coastline, it produced rainfall totals up to 4 in (100 mm) across Jalisco, which resulted in localized flooding. One man died there following a mudslide. Rainfall accumulations were generally similar across the Baja California Peninsula, though a peak value of was observed in El Triunfo. Many weather stations near Olaf's landfall location lost power upon the storm's final approach, but widespread tropical storm-force winds were nevertheless recorded. The strong winds damaged hotels, uprooted trees, and downed power lines. More than 190,000 customers across the Baja California Peninsula were without power at the height of the storm. Total damage was estimated at $10 million, primarily focused in La Paz and Los Cabos.
Hurricane Pamela
A tropical wave emerged into the eastern Pacific on October 8, and it swiftly organized into a tropical depression by 06:00 UTC on October 10. The system moved west-northwest, tracking parallel to the Mexico coastline initially after formation, and intensified into Tropical Storm Pamela six hours later.
Throughout Pamela's duration, the NHC highlighted the expectation of a potentially major hurricane rapidly intensifying up to the Mexico coastline. Despite these projections, the storm suffered first from moderate northerly wind shear and later from dry air intrusions, which caused the storm to fluctuate in intensity over the coming days. It became a hurricane around 06:00 UTC on October 12, weakened thereafter, and regained hurricane strength early the next day. Pamela maintained winds of 75 mph (120 km/h) as it recurved northeast ahead of a broad upper-level trough, and it made landfall at that intensity just north of Mazatlán, Sinaloa, at 12:30 UTC on October 13. Topographical and environmental effects caused Pamela to rapidly dissipate shortly before 00:00 UTC on October 14 over northern Mexico.
Although Pamela made landfall in a remote location, its effects were spread across large portions of northwestern Mexico. Across Colima and Nayarit, widespread rainfall accumulations of – with isolated totals up to – caused widespread flooding.
Numerous local communities were inundated or isolated, with individuals stranded and highways collapsed.
Crops suffered heavy losses. Gusty winds across Sinaloa damaged structures, either directly or from the uprooting of many trees. Across the Southern United States, the remnants of Pamela combined with a cold front, leading to a widespread area of rainfall totals, with locally higher amounts. Three people were killed as a result of Pamela, two in Texas when vehicles fell off a bridge into the Martinez Creek near San Antonio and one in Nayarit when one person was swept away into the
Acaponeta River
The Acaponeta River originates in the State of Durango, México and drains into the Pacific Ocean.
The river basin covers . From its beginning in Durango to where it crosses into Nayarit, the river is called Quebrada de San Bartolo; farther dow ...
.
Hurricane Rick
A collection of convection formed over Colombia, Panama, and adjacent waters of the Caribbean and East Pacific on October 16. The disturbance moved west without much change in organization until it developed into a tropical depression early on October 22. The system strengthened into Tropical Storm Rick within six hours of formation and continued to intensify amid very favorable environmental conditions as it moved generally north-northwest. Rick became a hurricane early on October 23, around which time the system developed a pinhole eye in microwave imagery. After reaching winds of 90 mph (150 km/h), the system abruptly weakened as its inner core structure eroded. However, the cyclone soon developed a large eye, and it reached a peak intensity of 105 mph (165 km/h) early on October 25. Rick maintained these winds as it made landfall in La Unión de Isidoro Montes de Oca, Guerrero, around 11:00 UTC. The storm weakened rapidly once inland and dissipated before 00:00 UTC on October 26.
Rick produced at least 4 in (100 mm) of rain across coastal sections of Guerrero and Michoacán, with a peak accumulation of 11.06 in (281 mm) in Petacalco and Coyuquilla in Guerrero. These rains prompted flash flooding that stranded cars and caused damage throughout the region, even well inland across the state of Morelos where one man was killed in Tepoztlán. Four rivers and streams overrun their banks across Zihuatanejo and Tecpan de Galeana, including the Petatlán River which cut off the Acapulco–Zihuatanejo federal highway. Many large trees were uprooted and some damage occurred to buildings between Ixtapa and Lázaro Cárdenas. Rick prompted the evacuation of 402 people and damaged 1,277 houses across 11 states and 700 municipalities. Nearly 184,000 homes lost power, especially concentrated in the states of Michoacán and Guerrero. Tens of millions worth in damage occurred.
Tropical Storm Terry
During the morning of November 1, a low pressure system formed over the southwestern Caribbean Sea, just north of
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Co ...
. The wave crossed
Costa Rica and emerged into the eastern Pacific on November 3. Convection swiftly organized as the system gradually became better defined that day, and the disturbance developed into Tropical Depression Eighteen-E at 15:00 UTC on November 4. However, dry air (some of which came from a Gulf of Tehuantepec gap wind event) entrained into the storm, keeping it weak and disorganized. The system remained disorganized while moving westward for the next few days, before organizing into Tropical Storm Terry at 21:00 UTC on November 7. However, Terry weakened to a tropical depression at 15:00 UTC on November 8 as it became less organized. Terry's circulation became better defined later that day, though its convection remained poorly organized. At 06:00 UTC on November 10, the depression opened up into a trough of low pressure.
Terry briefly affected Costa Rica and damaged around 11 houses and knocking over few trees. No fatalities were reported in Costa Rica but Terry's low form brought damage to Panama as well, injuring 1 person. One yellow alert was issued in
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
though there was no damage there. As a depression, a green alert was issued in the
Revillagigedo Islands
The Revillagigedo Islands ( es, Islas Revillagigedo, ) or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem. They lie approximately from Socorro Island south and southwest of C ...
though it was discontinued a few hours later.
Tropical Storm Sandra
At 19:00 UTC on November 1, the NHC began monitoring an area that was expected to develop into an area of low pressure several miles south of the southwestern coast of Mexico. The system organized further by 01:00 UTC on November 3, and further development prompted the NHC to begin issuing advisories on Tropical Depression Nineteen-E at 15:00 UTC on November 7. At 21:00 UTC on November 7, the depression was upgraded into a tropical storm based on
scatterometer
A scatterometer or diffusionmeter is a scientific instrument to measure the return of a beam of light or radar waves scattered by diffusion in a medium such as air. Diffusionmeters using visible light are found in airports or along roads to measur ...
data, despite the storm's appearance degrading, and the NHC assigned the storm the name ''Sandra''. However, Sandra weakened into a tropical depression 24 hours later, after
scatterometer
A scatterometer or diffusionmeter is a scientific instrument to measure the return of a beam of light or radar waves scattered by diffusion in a medium such as air. Diffusionmeters using visible light are found in airports or along roads to measur ...
data failed to find tropical storm-force winds. At 21:00
UTC on November 9, Sandra degenerated into a remnant low, after the storm's surface circulation was found to have opened up into a trough of low pressure.
Storm names
The following names were used for named storms that formed in the northeastern Pacific Ocean during 2021. This is the same list used in the
2015 season, with the exception of the name ''Pamela'', which replaced ''
Patricia
Patricia is a female given name of Latin origin. Derived from the Latin word ''patrician'', meaning "noble"; it is the feminine form of the masculine given name Patrick. The name Patricia was the second most common female name in the United State ...
''. The name ''Pamela'' was used for the first time this year. No names were retired from this list, so all will be used again in the 2027 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 degrees west and the
International Date Line, all names are used in a series of
four rotating lists. The next four names that were slated for use in 2021 are shown below. However, none of them were used.
Season effects
This is a table of all the storms that formed during the 2021 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
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 ...
, a
tropical wave, or a
low, and all the damage figures are in 2021 USD.
See also
*
Weather of 2021
The following is a list of weather events that occurred in 2021. The year began with La Niña conditions. There were several natural disasters around the world from various types of weather, including blizzards, cold waves, droughts, heat wave ...
*
Tropical cyclones in 2021
During 2021, 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, one ...
*
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 ...
*
List of Pacific hurricane records
*
2021 Atlantic hurricane season
The 2021 Atlantic hurricane season was the third-most active Atlantic hurricane season on record, producing 21 named storms and the second season in a row (third overall) in which the designated 21-name list of storm names was exhausted ...
*
2021 Pacific typhoon season
The 2021 Pacific typhoon season was the second consecutive to have below-average tropical cyclone activity, with twenty-two named storms, and was the least active since 2011. Nine became typhoons, and five of those intensified into super typho ...
*
2021 North Indian Ocean cyclone season
* South-West Indian Ocean cyclone seasons:
2020–21
The dash is a punctuation mark consisting of a long horizontal line. It is similar in appearance to the hyphen but is longer and sometimes higher from the baseline. The most common versions are the endash , generally longer than the hyphen b ...
,
2021–22
* Australian region cyclone seasons:
2020–21
The dash is a punctuation mark consisting of a long horizontal line. It is similar in appearance to the hyphen but is longer and sometimes higher from the baseline. The most common versions are the endash , generally longer than the hyphen b ...
,
2021–22
* South Pacific cyclone seasons:
2020–21
The dash is a punctuation mark consisting of a long horizontal line. It is similar in appearance to the hyphen but is longer and sometimes higher from the baseline. The most common versions are the endash , generally longer than the hyphen b ...
,
2021–22
Notes
References
External links
National Hurricane Center and Central Pacific Hurricane Center(website)
Servicio Meteorológico Nacional(website, in Spanish)
(website)
{{Tropical cyclone season, 2021
2021
File:2021 collage V2.png, From top left, clockwise: the James Webb Space Telescope was launched in 2021; Protesters in Yangon, Myanmar following the coup d'état; A civil demonstration against the October 2021 coup in Sudan; Crowd shortly after t ...
2021 EPac