The Weather Company has released its winter forecast of temperatures for December through February, and it's looking more and more likely to be a chilly winter for parts of the North.

"After an extended spell of above-normal temperatures across much of the U.S. during the past 18 months, the last few months have been characterized by below-normal temperatures across much of the eastern U.S., as a weak El Nino event has tried to emerge," said Dr. Todd Crawford, Chief Meteorologist at WSI, part of The Weather Company.

"While this El Nino event , most of our more skillful climate indicators suggest that very cold air will be in plentiful supply across western and central Canada this winter, with frequent border crossings into the northern U.S.," Crawford added. "Currently, we do not expect the kind of frequent atmospheric blocking in the North Atlantic that would result in in the eastern U.S. However, trends in some of the long-lead indicators suggest that this assumption may be challenged, and that the risk to the forecast in the eastern U.S. is towards the colder side."

Stu Ostro, senior meteorologist at The Weather Channel ( | ), notes that atmospheric blocking has been a major player in recent winters.

"That phenomenon of atmospheric 'blocking' by strong ridges of high pressure over Greenland and thereabouts is a key factor for winter weather downstream in the northeast United States, and it has been of overwhelming importance the past three winters," Ostro said.

"There was extreme blocking in 2009-10 and 2010-11, with arctic air and snowstorms repeatedly tackling the Northeast urban corridor. Then last winter, there was an equally extreme lack of Greenland blocking, in turn with relatively little cold air and snow in that and other parts of the U.S.

"Now, in autumn 2012, we've been seeing a tendency for a return of strong ridges over eastern Canada and Greenland. That pattern is what forced to take the track it did, and was favorable for '' the following week and this week's systems bringing more coastal flooding to the Outer Banks. We'll be watching very closely to see the extent to which this trend continues."

December Winter Forecast

(The winter forecast for December is for temperatures to be colder than normal across the North and warmer than normal across the South.)

December

The winter forecast for December calls for the coldest temperatures, relative to normal, to stretch from to Unseasonably warm weather is expected from to .

January Outlook

(The winter forecast for January is for temperatures to be colder than normal across the North and much warmer than normal for parts of the South, especially the Southwest.)

January

The winter forecast for January calls for below-normal temperatures across the North, from , to . Unseasonably mild weather should prevail from and to .

February Outlook

(The winter forecast for February is for temperatures to be colder than normal across the Midwest and warmer than normal in the Southwest.)

February

The winter forecast for February calls for temperatures well below average from Montana to the Great Lakes, including and . Warm weather continues in the Desert Southwest for places such as and .

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The Weather Company Winter Forecast is produced at WSI's Global Forecast Center in Andover, Massachusetts. As part of The Weather Company, WSI provides premier business-to-business weather services to media, aviation, and energy industries, as well as specialized forecasts for public distribution on The Weather Channel and weather.com. Over 200 meteorologists at The Weather Company's Global Forecast Centers in Atlanta, Andover, Houston, and Birmingham, England produce pinpoint daily forecasts for over 60,000 locations worldwide and other specialized forecasts and visualizations utilizing state-of-the-art and proprietary computer modeling, analysis, and distribution systems developed by The Weather Company's scientists and engineers.