Weather Underground Forecast for Saturday, May 18, 2013.

A strong low pressure system will bring active weather to the center of the nation on Saturday. The system will move off the Rockies and into the Plains, which will push a warm front into the Northern Plains and Upper Midwest, while it continues pulling a cold front southeastward across the Western states. Counter clockwise flow around this system will pull more moisture and energy into the Plains from the Gulf of Mexico, allowing for showers and thunderstorms to develop from Oklahoma through the Dakotas and into Minnesota. These areas are under a slight threat of severe weather development with strong winds, large hail, and heavy rainfall. Parts of western Nebraska and northwestern Kansas are under a moderate risk of severe thunderstorm development. This area has increased risk for tornado development on Saturday.

East of this activity, a weak trough slowly moves over the Eastern Valleys, allowing for a few more widespread showers and thunderstorms to pop up from the Southern Appalachians through the Mid-Atlantic states. Meanwhile in the West, moisture from the Pacific Ocean will allow for scattered showers with afternoon thunderstorms to persist for the Northern and Central Rockies. Severe storms are not likely in these areas. In the Southwest, gusty winds, warm temperatures, and dry conditions will maintain dangerous fire weather conditions on Saturday.