The nation's weather

AP News
Posted: Jul 28, 2011 5:03 AM
The nation's weather

Hot and active weather will continue in areas east of the Continental Divide on Thursday.

Showers, periods of heavy rainfall and thunderstorms in the Upper Mississippi Valley and the Upper Great Lakes will spread eastward into areas of the Northeast as a warm front moves into the Ohio Valley and a cold front advances into the Upper Great Lakes. Ample moisture availability and daytime heating will increase instability from the Central Plains through the southern Great Lakes and northern Ohio Valley, triggering a slight risk of severe thunderstorm development primarily during the afternoon and early evening hours. Severe storms in these regions will have the potential to produce damaging wind and possibly severe hail. Meanwhile, the moist and unstable airmass over the Southeast and Central Gulf Coast will linger and fuel more areas of showers, periods of heavy rainfall and clusters of thunderstorms. Elsewhere in the East, hot temperatures and scorching heat index values will persist in parts of the Southern and Plains and the Lower and Mid-Mississippi Valleys. This combination of hot temperatures and high humidity levels created a dangerous heat situation. Residents in these regions are encouraged to heed watches and warnings and take proper precaution against heat exhaustion.

In the West, chances of scattered to numerous thunderstorms will continue in parts of the Four Corners due to the continued moist and unstable environment over this region.

Temperatures in the Lower 48 states Wednesday ranged from a morning low of 30 degrees at Stanley, Idaho, to a high of 109 degrees at Hutchinson, Kan.