The nation's weather

AP News
Posted: May 20, 2011 4:42 AM
The nation's weather

Storms will persist across the Central U.S. on Friday, as a broad low pressure system makes its way into the Midwest from the Rockies.

Counter-clockwise flow around this system will create a strong warm front that will stretch from the Northern Plains and into the Mid-Mississippi River Valley. This system will pull ample moisture in from the Gulf of Mexico, allowing for periods of heavy rainfall and strong storms to develop. At the same time, the back side of this system will pull cold and dry air in from the Rockies, thus creating a cold front that stretches southward over the Central and Southern Plains. Moist air ahead of this cold front opposes dry air behind the cold front, which will create a favorable environment for severe storms. Heavy downpours are likely ahead of the front, while severe storms with large hail and tornadoes are expected to develop behind the front. These opposing airmasses will also create some strong winds. Expect gusts up to 30 mph across Texas, while the Dakotas will see 15 to 20 mph wind gusts.

In the East, a low pressure system that brought many days of rain to the Eastern Seaboard finally moves eastward and pushes offshore into the Atlantic Ocean. This will allow for high pressure to build over most of the Eastern half of the country, stretching from the Great Lakes to the Gulf of Mexico. The Southeast will remain dry and hot, with highs in the 80s and 90s, thus, fires will remain a threat across the region. The Northeast will see a few lingering clouds, with highs returning to the 70s. The extreme Northeast may see a few morning sprinkles, but significant rainfall is not likely.

Temperatures in the Lower 48 states Thursday ranged from a morning low of 21 degrees at Monarch Pass, Colo., to a high of 95 degrees at Laredo, Texas.