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Tropical Storm Olga was the fifteenth named storm of the 2007 Atlantic hurricane season. In the second week of December, after the official end of the hurricane season, a low developed east of the northernmost Lesser Antilles. It slowly acquired tropical characteristics, and late on December 10, the NHC declared it Subtropical Storm Olga while just north of Puerto Rico. It is the first post-season storm since Tropical Storm Zeta in the 2005 season, making the 2007 season one of the few with activity both before and after the official bounds of the hurricane season. Olga was only one of a few out of season landfalls, and was the deadliest post-season storm in the Atlantic Basin, with 40 deaths. The storm made landfall on December 11 on the eastern tip of the Dominican Republic. Later that evening, Olga transitioned into a tropical storm just after making landfall. Olga tracked over Hispaniola and emerged in the Caribbean Sea. Strong wind shear and dry air caused Olga to weaken into a remnant low early on December 13. The storm impacted many areas affected by Tropical Storm Noel a month earlier. In Puerto Rico, moderate rainfall caused one death. 37 fatalities were confirmed in the Dominican Republic, including twenty deaths due to the release of floodgates at a dam in Santiago Province. Two deaths were also reported in Haiti. ==Meteorological history== In the first week of December, a westward-moving upper-level low led to the formation of a broad surface trough well to the east of the northern Lesser Antilles.〔〔 With a strong ridge to its northeast, the trough tracked slowly westward, producing scattered convection and some cyclonic turning. On December 8 convection began to persist in association with the trough and an upper-level low. Early on December 9, officials at the Tropical Prediction Center began classifying the system using the Hebert-Poteat technique, and several tropical cyclone forecast models anticipated its development of tropical characteristics. The system, which consisted of a sharp trough with an area of gale force winds to its north, continued westward through an area of moderately warm sea surface temperatures. On December 10 a low-level circulation developed within the system, though its convection had become disorganized and well-removed from the center. Southerly wind shear left the structure asymmetric, and convection steadily increased closer to the center. With an upper-level low situated just south of the center, the National Hurricane Center classified it as Subtropical Storm Olga at 0300 UTC on December 11 while located about 55 miles (85 km) east of San Juan, Puerto Rico. Upon being classified as a subtropical cyclone, Olga maintained well-defined outflow, and located to the southeast of a strong ridge over the western Atlantic Ocean, the cyclone tracked west-southwestward.〔 The storm strengthened slightly while paralleling the north coast of Puerto Rico, and after an increase in convection near the center, Olga made landfall near Punta Cana, Dominican Republic at 1800 UTC on December 11. A Hurricane Hunters flight into the storm reported a tighter wind gradient and peak winds of 60 mph (95 km/h), and at 0000 UTC on December 12 the National Hurricane Center reclassified Olga as a tropical cyclone while it was still inland. Convection rapidly weakened as the storm crossed central Hispaniola, and upon reaching the Caribbean Sea the system lacked the convection required for the classification of a tropical cyclone; rainbands well to its northeast maintained stronger winds, though the center became ill-defined with dry air and strong wind shear. Late on December 12, convection increased slightly over the center, though by that time the cyclone weakened to tropical depression status. As significant convection failed to persist, the National Hurricane Center discontinued advisories on Olga earlier on December 13 while located about 80 miles (130 km) northwest of Kingston. Its remnants continued west-northwestward with a clear low-level circulation, producing scattered thunderstorms over Cuba and the Cayman Islands with its moisture extending northward into southern Florida. A small cluster of deep convection developed just east of the center, and the low-level circulation remained well-defined as it approached the coast of the Yucatán Peninsula. The remnants of Olga turned northward into the Gulf of Mexico as a cold front approached the center from the northwest. Late on December 16 and early on December 17, the low intensified as it approached the west coast of Florida, with sustained winds of tropical storm force, and gusts to hurricane force, being reported at Clearwater Beach. Ultimately, the approaching cold front absorbed the low as it moved across the Florida peninsula.〔 The cold front was associated with a powerful winter storm that affected much of Eastern America during that weekend and killed at least 25 across six US states and three Canadian provinces tapped Olga's moisture, drawing it northeastward mainly offshore the East Coast. 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 Olga (2007)」の詳細全文を読む スポンサード リンク
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