December blizzards in the Plains, Mid-Atlantic and New England and the current wave of icy air that has settled over much of the United States, particularly in the East as far south as Florida, are the precursors to what could be the worst winter in 25 years, according to AccuWeather.com Chief Long Range Forecaster Joe Bastardi.

“It’ll be like the great winters of the ’60s and ’70s,” Bastardi said.

Nearly the entire eastern half of the United States is enduring bitterly cold temperatures not experienced since 1985, according to AccuWeather.com, which is calling for another blast of “brutal arctic cold” to push south out of Canada and deep into the United States this week, reaching as far south as the western Gulf Coast by Thursday. Typically, when below-normal cold periods arrive in winter they are limited to one region, but this winter the colder air is stretching over larger portions of the country, Bastardi said.

The current cold wave has sent natural gas prices spiking in the Northeast, while pipelines have begun tightening restrictions with an eye to an extended period of below-normal temperatures and peak demand (see related story).

The winter of 2009-10 is shaping up to be similar to that of 1977-78, when nearly all of the United States east of the Rockies had a cold October followed by a warm November, with the cold returning in December, Bastardi said. January, February and March 1978 were all very cold relative to normal, according to Bastardi.

Last week AccuWeather.com said a weather pattern around Greenland would help a cold snap to settle over much of the eastern United States and portions of Europe for several weeks (see Daily GPI, Dec. 31, 2009). During the coldest periods, an area stretching from New England to Atlanta could see daytime highs in the 20s. According to AccuWeather.com, heating oil prices could increase based on the demand caused by the cold temperatures. Weather-related shortages were reported in the Mid-Atlantic region after two feet of snow fell in the Washington, DC, area Dec. 19.

AccuWeather.com’s forecast was somewhat at odds with a recent outlook from Andover, MA-based WSI Corp., which called for warmer-than-normal temperatures in January in the Northwest and the Northeast except Pennsylvania, New Jersey and Delaware (see Daily GPI, Dec. 22, 2009). According to the WSI forecast, almost all of the country can expect temperatures to average cooler than normal from January to March. WSI is forecasting 2,475 gas-weighted heating degree days during the three-month period, approximately 2.5% more than January-March 2009 and about 2% more than the 1971-2000 average.

The National Oceanic and Atmospheric Administration (see Daily GPI, Oct. 16, 2009) and Bastardi (see Daily GPI, Oct. 15, 2009) have each said colder weather will dominate portions of the East through February. In a contrary forecast, WxRisk.com has said it expects the Midwest — not the East — to experience the coldest temperatures relative to normal this winter (see Daily GPI, Oct. 27, 2009).

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