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Hurricane Gert was a large tropical cyclone that caused extensive flood damage throughout Central America and Mexico in September 1993. The seventh named storm and third hurricane of the annual hurricane season, Gert originated as a tropical depression from a tropical wave over the southwestern Caribbean Sea on September 14. The following day, the cyclone briefly attained tropical storm strength before moving ashore in Nicaragua and proceeding through Honduras. It reorganized into a tropical storm over the Gulf of Honduras on September 17, but weakened back to a depression upon crossing the Yucatán Peninsula. Once over the warm waters of the Bay of Campeche, Gert quickly strengthened into a Category 2 hurricane on September 20. The hurricane made a final landfall on the Gulf Coast of Mexico near Tuxpan, Veracruz, with peak winds of 105 mph (165 km/h). The rugged terrain quickly disrupted the cyclone's structure, and Gert entered the Pacific Ocean as a depression near the state of Nayarit on September 21. There, it briefly redeveloped a few strong thunderstorms before dissipating at sea five days later. Gert's broad wind circulation produced widespread heavy rainfall across Central America through September 15–17. Combined with saturated soil from Tropical Storm Bret's passage a month earlier, the rain triggered flooding and mudslides in numerous communities. In Costa Rica, the storm destroyed a national park and had a significant impact on the agricultural and tourism sectors. Much of the Mosquito Coast of Nicaragua and Honduras was affected, and many cities, villages, and crops in those countries were under water. Although Gert's highest winds occurred upon landfall in Mexico, the worst effects in the country were due to extreme rainfall across the Huasteca region, where as many as 31.41 inches (798 mm) of rain were recorded. Following the overflow of several major rivers, catastrophic flooding submerged extensive areas surrounding the Pánuco basin. Tens of thousands were forced to evacuate, and scores of structures were demolished in what was described as the region's worst disaster in 40 years. In the wake of the hurricane, the road networks across the affected countries were severely disrupted, hampering relief efforts in many regions. Government and emergency officials opened shelters and distributed food for the thousands that had lost their homes or sources of income. Throughout Central America and Mexico, 116 people were killed and 16 were left missing, while private property, infrastructure, and farmland were left in ruins, leading to over $170 million (1993 USD) in losses. ==Meteorological history== A tropical wave—an area of low pressure oriented north to south—moved off the African coast well south of Dakar on September 5, 1993, and tracked rapidly westward across the tropical Atlantic. Positioned at a relatively low latitude, the wave interacted with the Intertropical Convergence Zone, allowing for the enhancement of convection in its vicinity. It developed a weak low-pressure center at sea level, which passed directly over Trinidad on September 11. The majority of the system subsequently moved inland along the northern coast of South America, although it maintained its identity and emerged over the southwestern Caribbean Sea on September 13. Owing to favorable tropospheric conditions aloft, the system began showing signs of development as the deep convection organized into well-defined curved rainbands. Based on the increase in organization and the presence of a surface circulation, the National Hurricane Center (NHC) classified it as a tropical depression at 1800 UTC on September 14, about 105 miles (165 km) north of the northern coast of Panama.〔 The depression retained a large circulation during its formative stages, indicated by both satellite observations and data from rawinsondes in the region.〔 Its cloud pattern continued to coalesce, and the NHC upgraded it to Tropical Storm Gert at 0900 UTC on September 15. After tracking west-northwestward, the center of the storm moved ashore near Bluefields, Nicaragua, around 1800 UTC that day, with winds of 40 mph (65 km/h).〔 An interaction with land impeded further development, and Gert weakened back to a tropical depression six hours later. Despite the center being inland for nearly two days, a large part of the circulation stayed over the adjacent Caribbean and Pacific waters. This allowed Gert to remain a tropical cyclone while trekking northwestward through Nicaragua and Honduras,〔 defying the NHC's repeated forecasts of its dissipation over land. The cyclone moved into the Gulf of Honduras on September 17, restrengthening into a tropical storm soon thereafter. That same day, a mid- to upper-level trough over the eastern Gulf of Mexico caused the storm to turn to the north-northwest. Gert's duration over water was short lived; the storm moved back inland near Belize City the next day, granting it minimal opportunity for additional strengthening. Once inland, Gert began to feel the effects of a high-pressure ridge to its northwest, causing the storm to again turn west-northwest. After crossing the Yucatán Peninsula and decreasing in organization, it entered the Bay of Campeche offshore Champotón, Campeche, as a tropical depression late on September 18.〔〔 Gert restrengthened over open waters, as light wind shear allowed its deep convection to consolidate; by 0600 UTC the next day, the cyclone once again became a tropical storm. On September 20, data from a United States Air Force aircraft indicated that the storm had further strengthened into a hurricane with winds of 75 mph (120 km/h). Gert veered toward the west and slowed slightly owing to a shortwave trough to its north,〔 *〕 giving it more time to organize over water.〔 The cyclone attained its peak intensity as a Category 2 hurricane on the Saffir–Simpson scale, with winds of 100 mph (165 km/h) and a minimum pressure of 970 mbar (hPa; 28.64 inHg).〔 Around 2100 UTC on September 20, Gert made a final landfall at peak intensity on the coast of Mexico, just north of Tuxpan, Veracruz. Inland, the hurricane accelerated and weakened rapidly over the mountainous region of the Sierra Madre Oriental, diminishing to a tropical depression by September 21. Despite the degeneration, the large circulation remained intact as it crossed the country. Gert exited the coast of Nayarit and entered the Pacific Ocean later that day, where the NHC reclassified it as Tropical Depression Fourteen-E.〔〔 The remaining deep convection waxed and waned in intensity; satellite observations indicated the depression could have briefly been a tropical storm on September 22. It continued a west to west-northwestward motion for two days, though low-level flow steered it toward the southwest after the convection diminished. There was no redevelopment due to cool sea temperatures, and the system dissipated at sea on September 26. 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 Gert (1993)」の詳細全文を読む スポンサード リンク
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