Weather Underground Forecast for Wednesday, July 15, 2015
A cold frontal boundary will dip southward over the northern Plains, the upper Midwest and the Northeast on Wednesday, while monsoonal thunderstorms are expected across the Intermountain West.
A cold frontal boundary will sink southward over the northern Plains, the upper Midwest and the Northeast. Slightly cooler temperatures will trail this frontal boundary, bringing a bit of relief to the northern Plains and the Midwest. As this air mass collides with warm, humid air over the Plains, strong to severe thunderstorms will fire up over several states. Severe thunderstorms will be possible in North Dakota, northwest South Dakota, eastern Nebraska and northeast Kansas. These thunderstorms will be capable of producing large hail, dangerous straight line winds and isolated tornadoes. In addition, heavy rain will bring threats of flash flooding to eastern North Dakota, eastern Nebraska and western Iowa.
Meanwhile, thunderstorm activity will persist across the Northeast, the Mid-Atlantic and the Southeast. Severe thunderstorms will be possible over the southern half of Georgia and eastern South Carolina.
Out west, monsoonal moisture will aid in the development of showers and thunderstorms across the Four Corners and the Rockies. A ridge of high pressure over the eastern Pacific will keep conditions quiet from the Pacific Northwest to the Southwest. Temperatures will continue to jump into the triple digits across the Desert Southwest on Wednesday.
Temperatures in the Lower 48 states Tuesday have ranged from a morning low of 32 degrees at Truckee-Tahoe, Calif. to a high of 105 degrees at Needles, Calif.