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Cyclone Fani
Extremely Severe Cyclonic Storm Fani () was the worst tropical cyclone to strike the Indian state of Odisha since the 1999 Odisha cyclone. The second named storm and the first severe cyclonic storm of the 2019 North Indian Ocean cyclone season, Fani originated from a tropical depression that formed west of Sumatra in the Indian Ocean on 26 April. Vertical wind shear at first hindered the storm's development, but conditions became more favorable for Fani on 30 April. Fani rapidly intensified into an extremely severe cyclonic storm and reached its peak intensity on 2 May, with 1-minute sustained winds equivalent to a Category 5 major hurricane. Fani slightly weakened before making its landfall, and its convective structure rapidly degraded thereafter, degenerating into a remnant low on 4 May, and dissipating on the next day. It was succeeded by Cyclone Amphan in 2020 which caused a greater overall damage. Prior to Fani's landfall, authorities in India and Bangladesh moved at lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odisha
Odisha (English: , ), formerly Orissa ( the official name until 2011), is an Indian state located in Eastern India. It is the 8th largest state by area, and the 11th largest by population. The state has the third largest population of Scheduled Tribes in India. It neighbours the states of Jharkhand and West Bengal to the north, Chhattisgarh to the west, and Andhra Pradesh to the south. Odisha has a coastline of along the Bay of Bengal in Indian Ocean. The region is also known as Utkala and is also mentioned in India's national anthem, " Jana Gana Mana". The language of Odisha is Odia, which is one of the Classical Languages of India. The ancient kingdom of Kalinga, which was invaded by the Mauryan Emperor Ashoka (which was again won back from them by King Kharavela) in 261 BCE resulting in the Kalinga War, coincides with the borders of modern-day Odisha. The modern boundaries of Odisha were demarcated by the British Indian government when Orissa Province wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landfall (meteorology)
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 of arriving there. Tropical cyclone A tropical cyclone is classified as making landfall when the center of the storm moves across the coast; in a relatively strong tropical cyclone, this is when the eye moves over land. This is where most of the damage occurs within a mature tropical cyclone, such as a typhoon or hurricane, as most of the damaging aspects of these systems are concentrated near the eyewall. Such effects include the peaking of the storm surge, the core of strong winds coming ashore, and heavy flooding rains. These coupled with high surf can cause major beach erosion. When a tropical cyclone makes landfall, the eye usually closes in upon itself due to negative environmental factors over land, such as friction with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclone Gonu
Super Cyclonic Storm Gonu was an extremely powerful tropical cyclone that became the strongest cyclone on record in the Arabian Sea. The second named tropical cyclone of the 2007 North Indian Ocean cyclone season, Gonu developed from a persistent area of convection in the eastern Arabian Sea on June 1, 2007. With a favorable upper-level environment and warm sea surface temperatures, it rapidly intensified to attain peak winds of on June 4, according to the India Meteorological Department. Gonu weakened after encountering dry air and cooler waters, and early on June 6, it made landfall on the easternmost tip of Oman, becoming the strongest tropical cyclone to hit the Arabian Peninsula. It then turned northward into the Gulf of Oman, and dissipated on June 7, after making landfall in southern Iran, the first landfall in the country since 1898. Intense tropical cyclones like Gonu are extremely rare in the Arabian Sea, and most storms in this area tend to be small and dissipate q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 irregular in shape. This feature shows up in tropical cyclones of tropical storm or hurricane strength. How far the center is embedded within the CDO, and the temperature difference between the cloud tops within the CDO and the cyclone's eye, can help determine a tropical cyclone's intensity with the Dvorak technique. Locating the center within the CDO can be a problem with strong tropical storms and minimal hurricanes as its location can be obscured by the CDO's high cloud canopy. This center location problem can be resolved through the use of microwave satellite imagery. After a cyclone strengthens to around hurricane intensity, an eye appears at the center of the CDO, defining its center of low pressure and its cyclonic wind field. Tropic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye (cyclone)
The eye is a region of mostly calm weather at the center of tropical cyclones. The eye of a storm is a roughly circular area, typically in diameter. It is surrounded by the ''eyewall'', a ring of towering thunderstorms where the most severe weather and highest winds occur. The cyclone's lowest barometric pressure occurs in the eye and can be as much as 15 percent lower than the pressure outside the storm. In strong tropical cyclones, the eye is characterized by light winds and clear skies, surrounded on all sides by a towering, symmetric eyewall. In weaker tropical cyclones, the eye is less well defined and can be covered by the central dense overcast, an area of high, thick clouds that show up brightly on satellite imagery. Weaker or disorganized storms may also feature an eyewall that does not completely encircle the eye or have an eye that features heavy rain. In all storms, however, the eye is the location of the storm's minimum barometric pressure—where the atmospheric pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 imagery, this precipitation elongation is referred to as banded structure. Rainbands within tropical cyclones are curved in orientation. Rainbands of tropical cyclones contain showers and thunderstorms that, together with the eyewall and the eye, constitute a hurricane or tropical storm. The extent of rainbands around a tropical cyclone can help determine the cyclone's intensity. Rainbands spawned near and ahead of cold fronts can be squall lines which are able to produce tornadoes. Rainbands associated with cold fronts can be warped by mountain barriers perpendicular to the front's orientation due to the formation of a low-level barrier jet. Bands of thunderstorms can form with sea breeze and land breeze boundaries, if enough moisture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 intensities of their sustained winds. This measuring system was formerly known as the Saffir–Simpson hurricane scale, or SSHS. To be classified as a hurricane, a tropical cyclone must have one-minute-average maximum sustained winds at 10 m above the surface of at least 74 mph (64 kn, 119 km/h; Category 1). The highest classification in the scale, Category 5, consists of storms with sustained winds of at least 157 mph (137 kn, 252 km/h). The classifications can provide some indication of the potential damage and flooding a hurricane will cause upon landfall. The Saffir–Simpson hurricane wind scale is based on the highest wind speed averaged over a one-minute interval 10 m above th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 wind shear. Vertical wind shear is a change in wind speed or direction with a change in altitude. Horizontal wind shear is a change in wind speed with a change in lateral position for a given altitude. Wind shear is a microscale meteorological phenomenon occurring over a very small distance, but it can be associated with mesoscale or synoptic scale weather features such as squall lines and cold fronts. It is commonly observed near microbursts and downbursts caused by thunderstorms, fronts, areas of locally higher low-level winds referred to as low-level jets, near mountains, radiation inversions that occur due to clear skies and calm winds, buildings, wind turbines, and sailboats. Wind shear has significant effects on the control of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 masses in the Earth's atmosphere are highly modified by sea surface temperatures within a short distance of the shore. Localized areas of heavy snow can form in bands downwind of warm water bodies within an otherwise cold air mass. Warm sea surface temperatures are known to be a cause of tropical cyclogenesis over the Earth's oceans. Tropical cyclones can also cause a cool wake, due to turbulent mixing of the upper of the ocean. SST changes diurnally, like the air above it, but to a lesser degree. There is less SST variation on breezy days than on calm days. In addition, ocean currents such as the Atlantic Multidecadal Oscillation (AMO), can affect SST's on multi-decadal time scales, a major impact results from the global thermohaline cir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 winds of a tropical cyclone of at least in a 24-hour period. Necessary conditions External In order for rapid intensification to occur, several conditions must be in place. Water temperatures must be extremely warm (near or above ), and water of this temperature must be sufficiently deep such that waves do not churn deeper cooler waters up to the surface. Wind shear must be low; when wind shear is high, the convection and circulation in the cyclone will be disrupted. Dry air can also limit the strengthening of tropical cyclones. Internal Usually, an anticyclone in the upper layers of the troposphere above the storm must also be present for extremely low surface pressures to develop. This is because air must be converging towards the low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference layer in the atmosphere. Different lapse rates within dry and moist air masses lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to increased winds, cumulus cloud development, and decreased surface dew points. Moist convection leads to thunderstorm development, which is often responsible for severe weather throughout the world. Special threats from thunderstorms include hail, downbursts, and tornadoes. Overview There are a few general archetypes of atmospheric instability that are used to explain convection (or lack thereof). A necessary (but not sufficient) condition for convection is that the environmental lapse rate (the rate of decrease of temperature with height) is steeper than the lapse rate experienced by a rising parcel of air. When this condition is met, upward-displaced air parcels can become buoyant and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordinated Universal Time
Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used prime meridian) and is not adjusted for daylight saving time. It is effectively a successor to Greenwich Mean Time (GMT). The coordination of time and frequency transmissions around the world began on 1 January 1960. UTC was first officially adopted as CCIR Recommendation 374, ''Standard-Frequency and Time-Signal Emissions'', in 1963, but the official abbreviation of UTC and the official English name of Coordinated Universal Time (along with the French equivalent) were not adopted until 1967. The system has been adjusted several times, including a brief period during which the time-coordination radio signals broadcast both UTC and "Stepped Atomic Time (SAT)" before a new UTC was adopted in 1970 and implemented in 1972. This change also a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
