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The blizzard of 1977 was a deadly blizzard that hit the Western N.Y. state area upstate New York and Southern Ontario from January 28 to February 1, 1977. Daily peak wind gusts ranging from were recorded by the National Weather Service Buffalo Office, with snowfall as high as recorded in areas,〔 and the high winds blew this into drifts of .〔 There were 23 total storm-related deaths in western New York, with 5 more in northern New York.〔 Certain pre-existing weather conditions exacerbated the blizzard's effects. November, December and January average temperatures were much below normal. Lake Erie froze over by December 14; an ice-covered Lake Erie usually puts an end to lake-effect snow because the wind cannot pick up moisture from the lake's surface, convert the moisture to snow and then dump it when the winds reach shore. Lake Erie was covered by a deep, powdery snow; January's unusually cold conditions limited the usual thawing and refreezing, so the snow on the frozen lake remained powdery. The drifted snow on roadways was difficult to clear because the strong wind packed the snow solidly. In addition to the roads becoming impassable, motorists had to deal with vehicles breaking down due to the combination of very cold temperatures, very high winds and blowing snow. In the hardest-struck areas, snowmobiles became the only viable method of transportation. In western New York and southern Ontario, snow which was accumulated on frozen Lake Erie and snow on the ground at the start of the blizzard provided ample material for the high winds to blow into huge drifts – see ground blizzard. The combination of bitter cold, high winds, and blowing snow paralyzed areas affected by the storm. Lake Ontario rarely freezes over, which meant northern New York had to deal with considerable lake effect snow, which, when coupled with the existing snow cover and wind, created paralysis. ==Winter of 1976–1977== Weather conditions during the months leading up to the blizzard allowed the blizzard to have the impacts it did. A high-amplitude planetary wave pattern set up, which was very persistent from October 1976 through January 1977, and involved a ridge over western North America and a trough over eastern North America. In January 1977, this pattern persisted, with the pressure of the strong ridge over western North America being more than two standard deviations from the mean, while the strong trough centered over eastern North America was more than three standard deviations from the mean.〔 A strong blocking high developed over the Arctic Ocean during January, and this moved the polar vortex to southern Canada, south of its normal location. Strong northwest flow between the ridge and the trough resulted in a strong northwest flow in between, which ushered Arctic air into the central and eastern United States.〔 The circulation helped cause record cold for the winter over many portions of the eastern United States, with the Ohio Valley averaging more than below normal.〔 The severe winter was not limited to the northeastern United States; snow was observed in Miami, Florida, on January 20, and snow mixed with rain occurred in the Bahamas. 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「Blizzard of 1977」の詳細全文を読む スポンサード リンク
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