Antartica

Weather Underground Forecast for Wednesday, May 14, 2008.

The strong frontal system that brought severe weather to the Central and Southern U.S. on Tuesday will continue to advance eastward on Wednesday, producing more active weather from the Mississippi Valley to the Appalachians. The southern portion of the front extending across the Southern Plains will move southeast very slowly. Hence, a large portion of the Southern Plains eastward into the Lower Mississippi Valley is forecast to be the focus for severe thunderstorm development Wednesday. Large hail and a few tornadoes will be the primary threat. Otherwise, widely scattered showers and thunderstorms are anticipated along and ahead of the cold front. Expect the cold front to push into portions of the Mid-Atlantic Wednesday night and then across the East Coast Thursday.

High pressure holds across the Eastern U.S. through Wednesday, providing warm and sunny weather. A change is expected Thursday as the cold front moves through.

Out West, the residual Pacific moisture will trigger light rain and high elevation snow over the Pacific Northwest and northern Intermountain West. Expect precipitation to diminish by the evening hours. Farther south, an unusually strong ridge of high pressure will build over California and the Southwest Wednesday through Sunday, resulting in sunny and hot weather. Well above normal temperatures are expected with some record high temperatures possible in the interior.

Temperatures in the Lower 48 states Tuesday ranged from a low of 15 degrees at Stanley, Idaho to a high of 103 degrees at Laredo, Texas.