Antartica

Weather Underground Forecast for Tuesday, May 13, 2008.

The main weather story for the nation will be the active weather across the Midwest and Four Corners on Tuesday. The storm system in the upper Midwest with its cold front extending southwestward through the central Plains and Four Corners will gradually advance east and south Tuesday. This system combined with warm and moist air from the Gulf of Mexico will keep light to moderate rain continuing from the northern Plains and upper Midwest to portions of the Four Corners, with high elevation snow showers in the central Rockies. Moderate to strong thunderstorms are expected to develop especially in the afternoon and continue through the night. There is a risk of severe thunderstorms from Texas into the mid-Mississippi Valley, with the main threat of large hail, damaging winds, and possible a few tornadoes. Kansas and Missouri can expect a greater chance for tornado formation.

Moving to the West, light rain is expected to continue in far northwestern Washington early Tuesday. Expect precipitation coverage and intensity to gradually increase throughout the day as a Pacific system drops southeast from the British Columbia. Rain should become heavy at times in the afternoon and spread across Washington by Tuesday evening. The northern Plains will see rain developing as early as Tuesday night, continuing into Wednesday.

Elsewhere, scattered thunderstorms are expected in southern and eastern Texas during the day Tuesday as a weak front in the Gulf of Mexico extends into the region. Farther east, light rain is possible over the immediate mid-Atlantic coast early in the morning, but it should diminish rapidly as the storm system in the Western Atlantic departs.

Temperatures in the Lower 48 states Monday ranged from a low of 17 degrees at Limon, Colo. to a high of 105 degrees at Death Valley, Calif.