The Nation's weather
Wednesday, July 15th 2009, 1:43 pm
The main weather event for Wednesday is expected to be a system over the Central U.S. that is expected to advance eastward and bring widespread showers and thunderstorms from the Mississippi Valley and Central Plains to the Ohio Valley and Great Lakes. In particular, a risk of severe thunderstorms is anticipated over portions of the mid-Mississippi and Ohio valleys as well as the central High Plains through southern Kansas and northern Oklahoma. The main threat is forecast to be large hail and isolated damaging winds. Western portions of the Northeast and mid-Atlantic can expect showers and thunderstorms to develop as early as late Wednesday or Thursday morning as the front approaches.
Moving to the South, widely scattered showers and thunderstorms are expected to continue across portions of the Southeast and Gulf States as a weak front remains over the Southeast and the Gulf moisture continues to stream northward. Heavier precipitation is forecast near the front and along the Gulf Coast. Apart from the precipitation coverage, heat index values of 105 to 110 degrees should continue over parts of Kansas, Oklahoma, Texas, Arkansas and Louisiana during the afternoon hours.
Out West, forecasters call for a strong ridge of high pressure to hold firmly in place over the next few days, providing hot and dry weather across much of the West. Portions of the Desert Southwest, once again, can expect temperatures reaching over 110 degrees. On the other hand, moderate onshore flow will keep the coastal region on the cool side. Temperatures should stay mainly in the 60s and 70s.
Temperatures in the Lower 48 states Tuesday ranged from a low of 33 degrees at Mt. Washington, NH to a high of 115 degrees at Blythe, Calif.