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Hurricane Patricia ((:paˈtɾisia)) was the most intense tropical cyclone ever recorded in the Western Hemisphere in terms of barometric pressure, and the strongest globally in terms of reliably measured maximum sustained winds. Originating from a sprawling disturbance near the Gulf of Tehuantepec in mid-October 2015, Patricia was first classified a tropical depression on October 20. Initial development was slow, with only modest strengthening within the first day of its classification. The system later became a tropical storm and was named Patricia, the twenty-fourth named storm of the annual hurricane season. Exceptional environmental conditions fueled explosive intensification on October 22. A well-defined eye developed within an intense central dense overcast and Patricia grew from a tropical storm to a Category 5 hurricane in just 24 hours—a near-record pace. Early on October 23, Hurricane Hunters revealed the storm to have acquired record maximum sustained winds of 200 mph (325 km/h); a subsequent recon mission found a record low pressure of 879 mbar (hPa; 25.96 inHg). Late on October 23, Patricia made landfall in a significantly weakened state, though still at Category 5 intensity, near Cuixmala, Jalisco. It became only the second Pacific hurricane on record to make landfall at this intensity, after the 1959 Mexico hurricane. Interaction with the mountainous terrain of Mexico induced dramatic weakening, faster than the storm intensified. Within 24 hours of moving ashore, Patricia degraded into a tropical depression and dissipated soon thereafter late on October 24. The precursor to Patricia produced widespread flooding rains in Central America. Hundreds of thousands of people were directly affected by the storm, mostly in Guatemala. At least six fatalities were attributed to the event: four in El Salvador, one in Guatemala, and one in Nicaragua. Torrential rains extended into southeastern Mexico, with areas of Quintana Roo and Veracruz reporting accumulations in excess of . Damage in Chetumal reached 1.4 billion pesos (US$84.1 million). As a tropical cyclone, Patricia's effects in Mexico were tremendous; however, the affected areas were predominantly rural, mitigating a potential large-scale disaster. Violent winds tore roofs from structures and stripped coastal areas of their vegetation. Preliminary assessments indicate hundreds of homes to be destroyed and seven fatalities are linked to the hurricane, directly or indirectly. Total damage is estimated to be in excess of 3.3 billion pesos (US$199.1 million), with agriculture comprising the majority of losses. ==Meteorological history== On October 14, 2015, the U.S. National Hurricane Center began monitoring the possibility of tropical cyclogenesis over the far eastern Pacific, near the Gulf of Tehuantepec, as an area of low pressure was expected to form. This feature later consolidated on October 17, with a large area of convection—showers and thunderstorms—spanning several hundred miles from Central America westward over open waters. Under favorable environmental conditions, the low steadily organized and associated convection became more concentrated around its center. The system soon interacted with a Tehuantepec gap wind event on October 18, temporarily delaying development of the disturbance into a tropical depression. Drifting west-southwest in response to a ridge over the Gulf of Mexico, the disturbance consolidated throughout October 20. At 15:00 UTC, the system acquired sufficient convective organization to be classified ''Tropical Depression Twenty-E''. Upon its designation, the depression was situated roughly 445 mi (715 km) east-southeast of Acapulco, Mexico. Exceptionally favorable atmospheric conditions, consisting of light wind shear, sea surface temperatures of or higher, and high moisture levels yielded an environment highly conducive to rapid intensification.〔 A small inner-core soon developed and the depression intensified into a tropical storm by 03:00 UTC on October 21, at which time it was assigned the name ''Patricia''. For unknown reasons, the system unraveled substantially later that day with banding features dissipating and the low-level circulation becoming poorly defined. This phase was short-lived as convection blossomed over the storm late on October 21 and a central dense overcast formed over the center. An eye was noted early on October 22. The system reached hurricane strength by 09:00 UTC, featuring prominent outflow and well-defined banding features; rapid intensification ensued soon thereafter. Data from Hurricane Hunters investigating the cyclone indicated Patricia to have reached Category 4 status on the Saffir–Simpson hurricane wind scale by 18:00 UTC. By the early hours of October 23, a solid ring of cloud tops surrounded the hurricane's wide eye and signaled its intensification into a Category 5 hurricane. A clear northward turn took place followed by acceleration northeast.〔 Based on satellite analyses, Patricia was estimated to have acquired maximum sustained winds of 160 mph (260 km/h)—Category 5 on the Saffir–Simpson hurricane wind scale—and an estimated barometric pressure of 924 mbar (hPa; 27.29 inHg). In a 24-hour span, Patricia's winds increased by 100 mph (155 km/h). The rate of intensification was greater than that of any other Pacific hurricane on record in the satellite-era (1960s–present)—only Hurricane Linda in 1997 strengthened at a similar rate. Around 05:30 UTC, a reconnaissance aircraft measured flight-level winds of , yielding an estimated surface value of 185 mph (295 km/h), and a surface pressure of 892 mbar (hPa; 26.34 inHg). Patricia continued to deepen as the aircraft investigated the storm. The final observations from the Hurricane Hunters before they left the hurricane indicated the system to have attained winds of 200 mph (325 km/h) and a barometric pressure of 880 mbar (hPa; 25.99 inHg). Flight-level winds measured by the aircraft reached . Little change in strength took place through the remainder of October 23, with another reconnaissance mission around 18:00 UTC recording a slightly lower central pressure of 879 mbar (hPa; 25.96 inHg); this constitutes the maximum intensity of the hurricane.〔 The aircraft was battered by severe turbulence (via updrafts and downdrafts) and the crew experienced maximum g-forces of +3.0 and -1.5. An outer eyewall was noted in radar imagery, indicating the likely start of an eyewall replacement cycle. Following the investigation by recon, Patricia's eye became cloud-filled and weakening ensued. The violent, compact core of Patricia was roughly wide with the radius of maximum winds extending only .〔 At 23:15 UTC on October 23, the cyclone made landfall at Cuixmala, in the municipality of La Huerta, Jalisco—about 55 mi (85 km) west-northwest of Manzanillo—with winds of 165 mph (270 km/h) and an estimated pressure of 920 mbar (hPa; 27.17 inHg). This made Patricia the first hurricane to strike Mexico's Pacific coast as a Category 5 since an unnamed storm in 1959;〔 however, the status of the 1959 hurricane is disputed and it may have been weaker than originally assessed. Storm chasers in Emiliano Zapata, just inside the eye of Pactricia, measured a pressure of 937.8 mbar (hPa; 27.70 inHg); this is the lowest land-based pressure observation on record in the basin. Their observations also indicated an extraordinarily tight pressure gradient of 11 mbar (hPa; 0.32 inHg) per nautical mile. Rapid weakening ensued throughout October 24 as the hurricane traversed the Sierra Madre mountains; its eye disappeared from satellite imagery within hours of moving ashore. Patricia accelerated inland in between of a trough over Northwestern Mexico and the ridge over the Gulf of Mexico. Convection dramatically decreased in organization and the low- and mid- to upper-level circulation centers of the cyclone soon decoupled. The system degraded into a tropical depression by 15:00 UTC as little organized convection remained.〔 Patricia degenerated into a remnant low hours later. Unimpeded by the mountains of Mexico, the mid- to upper-level circulation of Patricia, accompanied by considerable moisture, continued northeast and interacted with a cold front over the western Gulf of Mexico. The new system produced flooding rains across large areas of Arkansas, Louisiana, Mississippi, and Texas. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hurricane Patricia」の詳細全文を読む スポンサード リンク
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