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Tropical Storm Bret was the deadliest natural disaster in Venezuela since the 1967 Caracas earthquake. The third tropical cyclone of 1993 Atlantic hurricane season, Bret formed on August 4 from a westward-moving, African tropical wave. Bret would later peak as a 60 mph (95 km/h) tropical storm as it neared Trinidad. It took an extremely southerly course through the Caribbean, passing over the coasts of Venezuela and Colombia. High terrain in the northern parts of those countries severely disrupted the circulation of the storm, and Bret had weakened to a tropical depression before emerging over the extreme southwestern Caribbean Sea. There, it restrengthened to a tropical storm and made landfall in Nicaragua on August 10, dissipating soon after. Bret's remnants reached the Pacific Ocean, where they ultimately became Hurricane Greg. Though Bret was only a weak tropical storm, it caused extreme flooding and nearly 200 deaths as it moved through South America, mostly in Venezuela. The first tropical storm to strike the country in 100 years, Bret deluged northern regions with of rainfall. The capital, Caracas, received of rain over just seven hours, resulting in widespread mudslides in the hills around the city that buried houses and carried away cars. There were 173 deaths in the country, and damage was estimated at US$25 million (1993 USD). Volunteers and firefighters helped storm victims cope with the damage, and workers cleared roads to restore transportation. Outside of Venezuela, Bret first affected Trinidad and Tobago, causing minor flooding and power outages. It passed just south of Curaçao, where the storm damaged the coral reef and the roofs of 17 homes. The storm later brushed northern Colombia, killing one person there, before hitting Central America. In Nicaragua, Bret killed 31 people and left US$3 million in damage, with many coastal towns isolated by floods. There was one death in neighboring Costa Rica and seven in Honduras, all due to flooding. In Central America, damage was compounded by Hurricane Gert moving through the region in early September. ==Meteorological history== Tropical Storm Bret originated from a tropical wave—a westward-tracking low-pressure area—that crossed the coast of Africa on August 1, 1993. Throughout its journey across the open Atlantic, the wave retained an impressive cloud structure with an area of deep convection. By August 4, the associated thunderstorm activity consolidated and organized into curved rainbands. The National Hurricane Center (NHC), noting the improving structure and sufficient support from Dvorak intensity estimates, reassessed the wave as a tropical depression at 12:00 UTC that day, the third such system of the annual hurricane season. At the time of its classification, it was located along the 10th parallel north over the central Atlantic, about 1,150 mi (1,850 km) west-southwest of the Cape Verde Islands. With a very resilient high-pressure area to its north, the depression continued moving due west at an unusually low latitude for most of its existence.〔 The system gradually organized due to low wind shear. After the outflow increased and the circulation became better established, the NHC upgraded the depression to Tropical Storm Bret early on August 5. Initially, the agency expected the storm would attain hurricane status while moving west-northwestward through the Caribbean Sea, although the storm would maintain its westward track. Early on August 6, Bret attained peak winds of 60 mph (95 km/h),〔 fueled by warm waters and increased banding around a central dense overcast. The circulation became exposed late on August 6, but the thunderstorms soon refired over the center.〔 At 07:00 UTC on the next day, Bret struck the island of Trinidad near Galera Point. The storm moved across the northern portion of the island,〔 and later made landfall in northeastern Venezuela near Macuro.〔 After hitting northeastern Venezuela, Bret continued westward through the extreme northern portion of the country. Around 20:00 UTC on August 7, the circulation emerged into the southeastern Caribbean Sea.〔 The circulation weakened and became poorly-defined, although the storm maintained stronger winds to the north. Despite the southerly inflow being disrupted by the mountainous terrain, Bret maintained its circulation while continuing westward, passing just north of Venezuela's capital Caracas. Around 08:00 UTC on August 8, the storm moved back onshore Venezuela near Morrocoy National Park in Falcón state.〔 Later that day, the NHC noted that there was "little if any circulation left to this system", although the agency continued issuing advisory due to the storm's heavy rainfall. However, a circulation emerged into the Gulf of Venezuela, which soon crossed into northeastern Colombia. There, the circulation neared the Pico Cristóbal Colón, the tallest mountain in Colombia with a peak of 18,947 ft (5,775 m). This caused the structure to deteriorate, and on August 9 Bret weakened to tropical depression status with the circulation "practically dissipated", according to the NHC. The Hurricane Hunters had difficulty finding a closed circulation, prompting the NHC to discontinue advisories at 15:00 UTC on August 9. After moving through the southwestern Caribbean Sea, Bret began to re-develop convection as upper-level conditions became more favorable.〔 By early on August 10, surface observations confirmed the presence of a low-level circulation, and the NHC re-issued advisories on the system. The convection continued to organize, prompting the NHC to upgrade Bret again to a tropical storm. The storm strengthened slightly further to a secondary peak of 45 mph (75 km/h). Around 17:00 UTC on August 10, Bret made its final landfall in southern Nicaragua near Bahia Punta Gorda. The circulation moved through the country and turned more to the west-northwest.〔 Operationally, it was believed that Bret survived after crossing Central America and entered the eastern Pacific, as NHC designated it Tropical Depression Eight-E. Post-storm analysis determined otherwise and Bret dissipated over western Nicaragua near the Pacific coast on August 11.〔 The remnants continued to the west-northwest, eventually developing into a tropical depression on August 15 off the west coast of Mexico. The system eventually became Hurricane Greg with peak winds of 135 mph (215 km/h), which lasted until August 28. 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「Tropical Storm Bret (1993)」の詳細全文を読む スポンサード リンク
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