Weather

The cool, dry air that has prevailed across the Northeast since the beginning of the week will begin to dissipate today as a south-to-southeast breeze ushers in more humid air.

Clouds, showers and thunderstorms will extend from the eastern Great Lakes to the Ohio Valley and the central and southern Appalachians. While the storms may produce damaging gusts in a few spots, torrential downpours are more likely to occur across the region. This may result in sudden poor visibility and flash flooding. Heavy, gusty thunderstorms are also expected along the Gulf and Southeast Coasts, but they should be much spottier than the northern storms.

Another batch of thunderstorms will extend from parts of Minnesota to the Dakotas. These storms will develop along the leading edge of a cooler air mass.

Most areas from the Plains to the Rockies, the Great Basin and the Pacific Coast can expect dry weather and sunshine. A hot afternoon is in store from the High Plains to the interior West. Along the Pacific beaches, morning low clouds and an ocean breeze will keep temperatures at moderate levels. There is still no sign of the southwestern United States monsoon, which tends to bring thunderstorms to the West around this time of year.

FOCUS: Hot And Humid Air Advances

A heat wave is expected to develop from the Midwest to the Northeast this weekend and into early next week. Hot and humid air will initially spread into eastern Canada on Saturday, before expanding into the Northeast.