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The February 2007 North America Winter Storm (otherwise referred to as the Valentine's Day Blizzard or Valentine's Day Storm) was a massive winter storm that affected most of the eastern half of North America, starting on February 12, 2007 and peaking on Valentine's Day, February 14. The storm produced heavy snowfalls across the midwestern United States from Nebraska to Ohio and produced similar conditions across parts of the northeastern United States, and into Canada in Ontario, Quebec and New Brunswick. Significant sleet and freezing rain fell across the southern Ohio Valley and affected portions of the east coast of the United States, including the cities of Boston, Baltimore, Washington, D.C., New York City and Philadelphia. The southern portion of the storm produced severe thunderstorms with numerous tornadoes reported. One tornado hit a subdivision of New Orleans that was still recovering from the effects of Hurricane Katrina, which hit the region in August 2005. In total, this storm system was responsible for 37 deaths across 13 U.S. states and Canadian provinces of New Brunswick, Ontario and Quebec. The NOAA classified the storm as a Category 3 "Major" storm.〔(【引用サイトリンク】 VALENTINE’S DAY WINTER STORM CLASSIFIED AS A CATEGORY 3 "MAJOR" STORM )〕 The National Weather Service has determined that this storm was one of the three largest snowstorms to hit the inland areas of the northeastern United States since 1940.〔 〕 == Prior to the storm == In sharp contrast to the mostly mild weather in the first few weeks of winter, the eastern half of the continent was under the influence of cold temperatures. Numerous areas had substantial snowfall deficits before this storm. After several weak Alberta clippers crossed the eastern half of the continent and brought occasional light snowfalls, a large dip in the Northern branch of the jet stream favored a more active pattern, which, as it connected with the southern branch, led to the development of the storm. An area of low pressure tracked across southeastern Canada during the 12th, which brought an arctic front across the Mid Atlantic region late on the 12th. As this occurred, a strong area of high pressure located across central Canada built down into the Northeast, allowing very cold air to spill southward ultimately leading to what is known as cold air damming. This occurs east of the mountains down through the Mid Atlantic states. Meanwhile, a Pacific storm slammed onto the California coast during the 11th and as it moved eastward, a new area of low pressure developed across southeastern Colorado and the Texas Panhandle. Previously, portions of the Great Lakes were hit by a significant lake effect snow event which dumped incredible amounts of snow over portions of central New York. Several areas received over 115 inches (over 2.5 m) of snow in a ten-day period just before the large winter storm as northwesterly winds and unfrozen lake surfaces due to the early winter warm weather favored the heavy snowfall. Several areas across Michigan and Ontario also received significant amounts of snow with locally 1 meter (3.3 ft) of snow east of Georgian Bay in Ontario.〔 〕 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「February 2007 North America blizzard」の詳細全文を読む スポンサード リンク
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