The nation's weather

AP News
Posted: Dec 24, 2009 6:00 AM

Energetic disturbances gathering in the Central U.S. were expected to create a major wintry precipitation event on Thursday.

These systems were forecast to draw yet more moisture from the Gulf of Mexico northward into the Plains, the Eastern Valleys, and the Upper Great Lakes. As this moisture moves into the North, it was expected to interact with a colder airmass to produce significant amounts of snowfall and freezing rain in the Midwest, accompanied by strong blustery winds producing drifting snow with reduced visibility.

Winter storm warnings and blizzard watches remained in effect through Christmas Day, and travel difficulties and delays were highly likely.

To the south of this storm, instability in the Lower Mississippi Valley was forecast to intensify as an area of low pressure in the Southern Plains moved into the saturated region before heading north. During it's progression, swaths of showers, heavy rainfall and strong to severe thunderstorms were expected to develop through the Mississippi Valleys. Once again, unsettling weather was expected to lead to travel difficulties.

Quieter weather activity was expected elsewhere. More dry and cool weather was forecast in the West as high pressure remained the dominant weather feature. Clearer and drier weather would return to the Northeast as low pressure exited further into the Atlantic Ocean.

Temperatures in the Lower 48 states Wednesday ranged from a low of -10 degrees at Doe Lake, Michigan to a high of 83 degrees at Brooks County, Texas.