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Tropical Storm Danny was a weak and disorganized tropical cyclone that formed in August 2009. The fourth tropical system and third named storm of the 2009 Atlantic hurricane season, Danny developed on August 26 from the interaction between a westward-moving tropical wave and an upper-level trough while situated east of the Bahamas. The storm never fully matured, and resembled a subtropical cyclone. It meandered generally northwestward before being absorbed into another weather system on August 29. Danny had only minor effects on land. However, it triggered high surf and rip currents from Florida through the Mid-Atlantic states, leading to the death of a 12-year-old boy in North Carolina. The cyclone's remnants contributed to widespread rainfall in the northeast United States. At one point, some weather forecasts predicted Danny to rapidly strengthen, and hit Nantucket as a Category 1 Hurricane, although this never occurred. Localized flooding was reported, particularly in Pennsylvania. It later caused heavy precipitation and power outages in Atlantic Canada. ==Meteorological history== Danny originated in a tropical wave that exited the west coast of Africa on August 18 and entered the Atlantic Ocean. Convective activity associated with the system briefly showed signs of organization on August 22; however, wind shear stunted further development. On August 24, shower activity once again increased as the disturbance interacted with an upper-level trough. On the afternoon of August 25, the National Hurricane Center assessed a high chance of tropical cyclone formation within 48 hours. That same day, a Hurricane Hunters mission into the system revealed a broad area of tropical-storm force winds, but no closed circulation center. However, around 0900 UTC on August 26, satellite imagery and QuikSCAT information indicated that a closed circulation had formed. While situated about to the east of Nassau, Bahamas, the feature was declared a tropical storm—skipping the tropical depression stage.〔 Due to the interaction of the initial wave and the upper-level trough, Danny maintained a "non-classical" structure resembling that of a subtropical cyclone.〔 Even after its designation as a tropical storm, the storm was highly disorganized. Little or no deep thunderstorm activity surrounded the center, and the highest winds in relation to the cyclone were confined to a rainband in the northern semicircle. The storm moved erratically northwestward throughout the day, strengthening slightly.〔 Danny's center reformed several times, making it difficult to determine its exact forward motion. By early on August 27, the tropical storm became slightly better organized, although the most intense winds were still removed from the center. Danny peaked with maximum sustained winds of 60 mph (95 km/h) and a minimum pressure of 1006 mbar (hPa; 29.71 inHg). It held this strength for about 12 hours before wind shear caused the storm to gradually weaken as it meandered northward.〔 By August 28, Danny further deteriorated, and reconnaissance aircraft found that it was barely a tropical storm. After stalling during the afternoon, the center resumed a north or north-northwestward drift. A strong upper-level trough moving through the southeastern United States forced Danny northeastward, which also triggered the formation of another low pressure system near the coast of North Carolina early on August 29. Although this low formed within Danny's cyclonic envelope, satellite imagery indicated that it did not have the characteristics of a tropical cyclone. Therefore, it is not considered to be a continuation of Danny. The new low caused the tropical storm to degenerate into a trough about 275 mi (445 km) southeast of Wilmington, North Carolina, and Danny's remnants were absorbed into a developing frontal zone shortly thereafter.〔 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 Danny (2009)」の詳細全文を読む スポンサード リンク
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