The nation's weather

AP News
Posted: Apr 15, 2011 4:57 AM
The nation's weather

A trough of low pressure will continue kicking up storms across the Central U.S. on Friday.

The system will persist on its eastward path, moving from the Central Plains to the Mississippi River Valley. Counter-clockwise flow around this system continues pushing warm and moist air northward from the Gulf of Mexico, which produces a strong warm front that stretches up the Ohio River Valley and into New England. Periods of heavy rain and thunderstorms are expected to develop along this front. At the same time, the back side of this system pulls cool and dry Canadian air into the Plains. This creates a cold front that sweeps eastward from the Southern Plains to the Gulf of Mexico. The drastically opposing air masses will allow for severe storm development over the Lower Mississippi River Valley. Severe storms will produce strong and damaging winds, large hail, heavy downpours and even tornado development is likely.

In the West, more wet weather is expected as another low pressure system dips in from the Gulf of Alaska. The system will continue pushing a cold front onshore, which will move reach into northern California on Friday evening. The northern track of this system is expected to bring heaviest precipitation to the Pacific Northwest, with periods of heavy snow showers persisting across the Cascades and moving into the Northern Rockies.

Temperatures in the Lower 48 states Thursday ranged from a morning low of 12 degrees at Stanley, Idaho, to a high of 91 degrees at Laredo, Texas.