In the East, a cold front will continue to advance eastward across the East Coast on Wednesday, bringing showers and thunderstorms across the region.
Parts of the Mid-Atlantic and southern New England should see clearing later in the day as the system gradually moves offshore. By Thursday morning, most of the Northeast and Mid-Atlantic should clear up. The southern portion of the front is expected to become nearly stationary over the Gulf States, keeping showers and thunderstorms going Wednesday through Thursday. Also, it will lift northward across the Plains. As this occurs, the heat in the Southern Plains will creep up from Texas to Montana and the Dakotas, causing temperatures rising into 90s and 100s in the afternoon. This heat wave may last into Saturday.
Moving to the West, the Pacific system that pushed ashore Tuesday will move into the Intermountain West on Wednesday, triggering widely scattered showers and thunderstorms. Afternoon and evening storms are possible to be severe. There is a slight risk of severe thunderstorms in portions of Montana. Temperatures in the West Coast, especially California, will bounce back to near average. In fact, afternoon temperatures are forecast to reach triple digits by the weekend across the interior of California.
Temperatures in the Lower 48 states Tuesday ranged from a morning low of 32 degrees at West Yellowstone, Mont., to a high of 111 degrees at Needles, Calif.