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Cyclone Geralda (also known as Intense Tropical Cyclone Geralda) was a powerful tropical cyclone that caused catastrophic damage in Madagascar in late January 1994, among the strongest to hit the country. It originated from an area of low pressure over the Indian Ocean on January 25. Over the following few days, the depression underwent gradual intensification, reaching its peak intensity with ten-minute sustained winds of 200 km/h (125 mph) on January 31. Cyclone Geralda made landfall near Toamasina, Madagascar after weakening from its peak intensity. Within hours of moving onshore, the system had substantially weakened, and by February 5, Geralda had degenerated into a land depression, and it became extratropical three days later. Geralda was the second cyclone in as many months to strike eastern Madagascar, after Daisy in January. Geralda produced wind gusts as strong as , which were the highest worldwide for several decades. The cyclone also dropped heavy rainfall that caused flooding, particularly in valleys. About 80% of the city of Toamasina was destroyed, including most schools, homes, and churches. The cyclone heavily damaged roads and rail lines, which later disrupted relief efforts. In the capital Antananarivo, Geralda killed 43 people after flooding many houses. Overall, more than 40,000 homes were destroyed, leaving 356,000 people homeless. Nationwide, the cyclone killed 231 people and caused over $10 million in damage (1994 USD). Relief work in the storm's aftermath was hampered by lack of coordination, and the Malagasy military were deployed to help storm victims. Few stocks were pre-positioned, causing food prices to rise greatly. Several countries and departments of the United Nations donated money or supplies to the country. ==Meteorological history== In late January 1994, the south Indian Ocean Intertropical Convergence Zone produced widespread convection from the eastern coast of Africa to Indonesia. Late on January 25, the Joint Typhoon Warning Center (JTWC) began monitoring a low-pressure area about halfway between Madagascar and Indonesia, later giving it the designation "13S". The following day, the Météo-France on Réunion (MFR) classified the system as a tropical disturbance. By that time, the system had developed an organized area of convection with curved rainbands and was strengthening quickly; early on January 28, it developed a central dense overcast. In response, MFR upgraded the system to Moderate Tropical Storm Geralda. At that time, the storm was moving generally west-southwestward due to a ridge extending from Madagascar to the Mascarene Islands. High water temperatures fueled further development, first into a moderate tropical storm late on January 28 and then into a tropical cyclone 24 hours later.〔 By then, the JTWC had upgraded Geralda to the equivalent of a minimal hurricane.〔 Continuing generally to the west-southwest, Geralda intensified further, and MFR upgraded it to intense tropical cyclone status on January 30. The cyclone developed a well-defined eye in diameter and grew to a size of in diameter.〔 At 0600 UTC on January 31, the JTWC estimated peak 1–minute sustained winds of 270 km/h (165 mph), equivalent to a Category 5 hurricane on the Saffir-Simpson scale.〔 Six hours later, Geralda's appearance on satellite imagery warranted a Dvorak rating of 7.0. Based on this, MFR estimated a minimum barometric pressure of and peak 10–minute winds of 205 km/h (125 mph),〔〔 just shy of very intense tropical cyclone status. At that time, gusts were estimated at over . Geralda had intensified from a tropical disturbance to its peak intensity in only five days, which was described by MFR as "an exceptional phenomenon". Near peak intensity, the center of Geralda passed about northwest of Tromelin Island, offshore eastern Madagascar.〔 After maintaining its peak winds for about 18 hours, Geralda weakened slightly while approaching eastern Madagascar. At 0600 UTC on February 2, MFR estimated the winds were around 175 km/h (110 mph).〔 At about 1100 UTC that day, the cyclone made landfall just north of Toamasina as an intense tropical cyclone, where a pressure of was reported.〔 Officials considered Geralda the strongest storm to hit the country since a cyclone in March 1927.〔 Geralda weakened rapidly over the mountainous terrain of Madagascar, passing over the capital Antananarivo late on February 2; both the JTWC and MFR had downgraded the cyclone to tropical depression status by the next day.〔〔 About 30 hours after its first landfall, Geralda briefly emerged into the Mozambique Channel late on February 3. However, a trough soon turned it to the south, and Geralda crossed over western Madagascar, reaching open waters on February 5.〔 By that time, the winds had decreased to 45 km/h (30 mph).〔 An approaching polar trough turned Geralda to the southeast on February 6, and the cyclone became extratropical two days later. MFR continued tracking the remnants of Geralda until February 12.〔 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「Cyclone Geralda」の詳細全文を読む スポンサード リンク
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