After pummeling the upper Midwest on Wednesday, severe thunderstorms are expected to threaten areas farther south and east from lower Michigan to the Texas Panhandle. Damaging wind, hail and heavy rain will be the main threats. Thunderstorms will also affect areas across the Southeast. While some thunderstorms could become strong, widespread severe weather is not expected across this region. Much of the Northeast and mid-Atlantic states will stay dry but steamy as temperatures rise well above normal and humidity remains high. Dry weather will also span the Ohio and mid-Mississippi valleys, as well as much of Oklahoma and Texas. Farther west, afternoon thunderstorms will develop across parts of Colorado, New Mexico, Arizona and the mountains of California. Sizzling heat will bake much of the Southwest deserts and California. Much of the rest of the West will stay dry with sunshine. Temperatures will be slightly above normal on the northern High Plains. The tropics will remain quiet. Several tropical waves are spread across the open Atlantic, but none are expected to develop in the next few days. FOCUS: FUEL FOR A HURRICANE The fuel for big hurricanes comes from heat stored in the ocean. The heat is released into a developing storm through evaporation and condensation. The warmer the sea surface, the more effective this process is, resulting in stronger storms. 