WEATHER UNDERGROUND
For The Associated Press

Weather Underground Forecast for Wednesday, September 03, 2014

A cold front will extend from the middle Mississippi Valley to the Northeast on Wednesday, while a separate cold front will stretch from the West Coast to the northern Plains.

A cold frontal boundary will extend across the middle Mississippi Valley, the Tennessee Valley, the Mid-Atlantic and the Northeast on Wednesday. As this cold front collides with a warm, moist air mass, showers and thunderstorms will develop over a handful of states. The strongest will pop up across the Tennessee Valley and New England. An onshore flow from the Gulf of Mexico will also initiate thunderstorms across the eastern Gulf Coast and the Southeast. In addition, Tropical Storm Dolly will bring stormy weather to the western Gulf Coast and parts of southern Texas.

Meanwhile, warm, humid air will continue to surge across the nationÂ’s midsection, which will trigger strong to severe thunderstorms over the upper Midwest. Severe thunderstorms will be possible over Minnesota and northwest Wisconsin. These thunderstorms will be capable of producing large hail, dangerous straight line winds and isolated tornadoes. Heavy rain associated with these thunderstorms will also bring a threat of flash flooding to the upper Mississippi Valley.

Just to the west, a cold front will stretch from northern California to northeast Montana. Showers and thunderstorms will likely develop across the Pacific Northwest and the upper Intermountain West on Wednesday. High pressure will keep conditions clear across the Southwest.

Temperatures in the Lower 48 states Tuesday have ranged from a morning low of 28 degrees at Yellowstone, Wyo. to a high of 110 degrees at Death Valley, Calif.

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