Fox News Weather Center

Severe Storms, Flooding to Threaten DC, NYC, Pittsburgh

Starting on Sunday, the Northeast and mid-Atlantic will be faced with severe thunderstorms and flooding downpours on multiple days before the new week ends on a more refreshing note.

A quiet start to the weekend will give way to the adverse weather threat that will span Sunday through at least Tuesday.

That is the last thing those still cleaning up after last Tuesday's deadly severe weather wants to hear.

Severe weather will return to upstate New York, northern and western Pennsylvania and back through the lower Midwest states as soon as Sunday, mainly in the afternoon and evening, as a cold front slices into the steamy air.

An increase in humidity will fuel this first round of violent thunderstorms.

Syracuse and Binghamton, New York; Erie, Pittsburgh and State College, Pennsylvania, will join Columbus and Cincinnati, Ohio and St. Louis, in bracing for the severe thunderstorms to end the weekend.

Less-intense thunderstorms will dot the I-95 corridor on Sunday afternoon. Such thunderstorms will still be disruptive and hazardous to those with outdoor activities due to the danger of lightning strikes.

As the front sinks southward, the severe weather danger will focus on southwestern New England and more of the mid-Atlantic, as well as the Ohio and Tennessee valleys on Monday. As is typical, the afternoon and evening hours will likely prove to be more active than the morning.

Binghamton, Pittsburgh and Columbus will become the target of yet another round of severe weather this day. Monday's threat zone also encompasses New York City, Philadelphia, Washington, D.C., Roanoke, Virginia, and Nashville, Tennessee.

The strongest thunderstorms Sunday through Monday will produce powerful winds and downpours. Such winds could down trees, lead to property damage and cause power outages.

The downpours may not only trigger flash flooding, but also will cause hazards to motorists by dramatically reducing visibility and heightening the risk of vehicles hydroplaning. Significant delays and even ground stops are possible at airports.

"The pattern may also bring thunderstorms with hail in some communities and perhaps isolated tornadoes," stated Senior Meteorologist Alex Sosnowski.

An end to the severe weather threat will not come with the close of Monday. Instead, a stronger cold front that marks the leading edge of Septemberlike cool air plunging into the Midwest will spark more heavy thunderstorms throughout the East and South on Tuesday.

Additional flash flooding problems may unfold, especially where thunderstorms are slow moving, repeat over the same area and/or track over areas that first become soaked by the storms on Sunday or Monday. meteorologists are also concerned for some of the thunderstorms to turn severe, mainly from Virginia to Vermont and New Hampshire. The magnitude of the severe weather will be dependent on morning cloud cover and thunderstorms.

"There is a chance that torrential downpours linger along the beaches and into eastern New England through Wednesday," added Sosnowski.

Residents and visitors should continue to check back with for the latest details on the impending flooding and severe weather dangers.

Less humid and quieter weather will return later in the week with temperatures set to be held below normal despite this time of year commonly being the hottest. The greatest departures from typical mid-July highs will likely be around the Appalachians and eastern Great Lakes.