The nation's weather

AP News
Posted: May 10, 2011 4:38 AM
The nation's weather

Wet weather will persist across the northern U.S. on Tuesday as a low pressure system slowly moves across the U.S. and Canadian border.

The system that moved over the Rockies and into the Plains will take a northward turn and move northeastward into Manitoba. Flow around this system continues pulling warm and moist air in from the Gulf of Mexico, thus producing a warm front that will make its way over the Great Lakes and into Ontario. The tail end of this front will stretch over the Midwest and into the Eastern Valleys, were it will kick up widespread scattered showers and thunderstorms. Some of these storms may turn severe from the Ohio River Valley to the Mid-Atlantic states. At the same time, counter-clockwise flow around this system will push moisture into the Northern Rockies. Thus, a few more rain and snow showers will develop across Montana and Wyoming.

Meanwhile, behind this system in the West, a short ridge of high pressure will bring drier conditions with slightly warmer temperatures to the West Coast. Another low pressure system spinning in the Gulf of Alaska will quickly dip southeastward and approach the West Coast, but not yet produce showers over the region.

In the Southwest and Southern Plains, high pressure will continue bringing warm, dry, and windy conditions. This will create more dangerous fire weather conditions as low humidity and strong winds allow for rapid fire spread. Fire weather advisories will remain in effect from New Mexico to Kansas and Oklahoma.

Temperatures in the Lower 48 states Monday ranged from a morning low of 23 degrees at Mt. Washington, N.H., to a high of 102 degrees at Childress, Texas.