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The Winter 1985 cold wave〔(Cold enough for snow, and more's on the way )〕 was a meteorological event, the result of the shifting of the polar vortex further south than is normally seen.〔 Blocked from its normal movement, polar air from the north pushed into nearly every section of the eastern half of the United States and Canada, shattering record lows in a number of areas.〔 The event was preceded by unusually warm weather in the eastern U.S. in December 1984, suggesting that there was a build-up of cold air that was suddenly released from the Arctic, a meteorological event known as a Mobile Polar High, a weather process identified by Professor Marcel Leroux.〔(A Lesson in Meteorology: Mobile Polar Highs )〕 ==Meteorological synopsis== From Sunday, January 20, to Tuesday, January 22, 1985, the polar vortex, coupled with a large ridge of high pressure, moved polar air into the United States as far south as Florida.〔 Unlike most cold air systems, a pattern of self-modification did not immediately occur, i.e. seasonable temperatures were absent for a number of days, a rarity in forecasting.〔 The Arctic air mass started moving into the United States on the evening of January 19 and the morning of January 20. An early victim of the air mass was the city of Chicago, which recorded a record low of , coupled with winds to produce a wind chill of , also never recorded before. The wind chill calculation was adjusted in 2001, which would make the value about on the new scale.〔(January Weather Trivia Statements )〕 St. Louis saw a low of . Pittsburgh woke up that morning to find a low of , the coldest morning since 1899.〔(NWA Pittsburgh statistics )〕 In Cincinnati, the morning temperature of tied for the fourth-lowest minimum temperature in the city's history, outdone by a cold mass the year before and a blizzard in 1977.〔(RECORDS FOR CINCINNATI )〕 Cleveland fell to , which was at the time a record.〔(Cleveland Normals and Records for January )〕 Memphis recorded a low of , setting a record low for that day. The coldest temperature in the contiguous states on Jan. 21 was , in the unlikely location of Akron, Ohio.〔USA Today, January 22, 1985, p. 12A〕 The mass moved east and south during the day on January 20, resulting in frigid air for most of the Eastern Seaboard starting on the morning of January 21. New York City's Central Park recorded a low of , breaking that date's record.〔(CENTRAL PARK NEW YORK CITY RECORDS 1869-2008 )〕 Washington National Airport set a record of for the morning of January 21 and a record low for the prior date of .〔(DAILY NORMALS AND RECORDS FOR THE MONTH OF JANUARY FOR WASHINGTON DC )〕 It was the Southern United States that felt the biggest brunt, unaccustomed as they are to the Northern states' winter air. Roanoke, Virginia set a record low of , and the campus of the University of Tennessee at Knoxville, Tennessee, recorded a record low of .〔 Tennessee's state capital, Nashville, dropped to , while all-time records were set well into interior sections of the deep South, such as in Charlotte,〔 in Macon, Georgia,〔 in Jacksonville, Florida,〔 and in Gainesville, Florida〔(All-Time Extremes (Gainesville) )〕 (coldest since in 1899). Atlanta saw a low of , setting a record for the month of January and for the 20th century, missing by just one degree the all-time record (since 1879) set in February 1899.〔(Average Weather for Atlanta, GA )〕 Even Miami, whose average low in late January is , recorded a low of on the 21st and on the 22nd, both record lows for the date, the latter being one of only 10 times the city has been that cold since 1895.〔()〕〔http://voices.yahoo.com/all-time-record-hottest-coldest-temperatures-ever-12098217.html〕 Ferocious cold in February 1985 set two more state record lows in the Mountain West. Utah's was the second-coldest temperature ever recorded in the "lower 48" states, just above Montana's record of in 1954. Colorado's broke the old record of , also on February 1. 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「Winter 1985 cold wave」の詳細全文を読む スポンサード リンク
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