The nations weather

AP News
Posted: Sep 26, 2011 5:16 AM
The nations weather

More active weather is expected in the eastern half of the nation and in the Northwest on Monday.

A lingering low pressure system over the Great Lakes will support showers and thunderstorms in Wisconsin and Michigan. The system will also support stronger storms along and ahead of a slow moving frontal boundary that will extend from the Ohio and Tennessee Valleys into the Lower Mississippi Valley and the Southern Plains. Prolonged scattered showers and periods of heavy precipitation will lead to flood concerns in the Ohio Valley and the southern portion of the Great Lakes.

Ahead of this system, a moist, tropical airmass in the eastern third of the nation will interact with a weak frontal boundary along the Mid-Atlantic coast. This will translate into scattered showers and thunderstorms during the afternoon.

A cold front will push across the Northwest with showers and chances of thunderstorms. Behind this system, a second disturbance will approach the Pacific Northwest with moist onshore flow. This disturbance will spread more rainy and windy weather into the Pacific Northwest.

Temperatures in the Lower 48 states Sunday ranged from a morning low of 26 degrees at West Yellowstone, Mont., to a high of 105 degrees at Brady, Texas.