San Francisco, CA

Weather Underground Forecast for Tuesday, August 06, 2013.

Rain and strong thunderstorms will continue from parts of the Plains into the East on Tuesday.

In the Central U.S. , a nearly stationary frontal boundary over the Central Rockies into the Central High Plains combined with a wave of low pressure lingering over the Central Plains will support continued widespread showers and storms for parts of the Nebraska and the Central Plains into Missouri. Ample moisture and instability across the area will likely lead to flash flooding in parts of Kansas and Missouri. Additional, lighter showers and thunderstorms will continue ahead of an associated warm front extending into the Southeast.

Meanwhile, to the north, light to moderate showers will return to the Northern Plains and Midwest as a cold front drops into the North-Central U.S. from the Canadian Prairie. Scattered severe storms appear likely along and ahead of the cold front. The Storm Prediction Center has issued a slight risk of severe storms for areas from eastern South Dakota and Nebraska eastward into far western Wisconsin and northwestern Illinois. While the primary threats of severe weather in these areas are large hail and damaging wind gusts, tornado development cannot be ruled out.

Elsewhere in the eastern half of the nation, cool, autumn-like temperatures continue for the Midwest into the Northeast and Mid-Atlantic. In addition to cool weather, showers and thunderstorms are expected from parts of Michigan southeastward into the northern stated of the Mid-Atlantic region.

Out West, monsoonal moisture will kick up afternoon and evening showers and thunderstorms in areas of the Four Corners.