Fox News Weather Center

Damaging Storms Sunday: Virginia to Pennsylvania

Powerful thunderstorms threaten to close out this extended holiday weekend from Virginia to Pennsylvania, creating hazards to residents and travelers.

Thunderstorms capable of unleashing downpours and damaging winds will erupt on Sunday afternoon from northern Virginia to central and eastern Pennsylvania.

The majority of the strongest thunderstorms should remain west of the I-95 cities of Washington, D.C., Philadelphia and New York City. Instead, the I-81 corridor will be targeted.

This includes the cities of Winchester, Va., Hagerstown, Md., and Gettysburg, Harrisburg and Lancaster, Pa.

The danger zone also extends westward to Frostburg, Md., and Altoona, Pa., and will shift to Allentown and Scranton, Pa., during the evening hours.

Downpours from the heaviest thunderstorms may not only trigger flash flooding, but will also create dangers for motorists by dramatically reducing visibility and setting the stage for vehicles traveling at highway speeds to hydroplane.

Drivers may be forced to find alternate routes if some roads become littered by trees and/or branches downed by the strong thunderstorm winds.

In addition to I-81, those planning to head home from their Independence Day destinations via I-70, I-76, I-83, I-84, I-99 and I-476 on Sunday afternoon and evening lie in the path of the violent thunderstorms.

Anyone enjoying last-minute holiday celebrations this Sunday should also keep an eye to the sky and seek shelter immediately if a storm-related warning is issued.

The same can be said as soon as thunder is heard; you are then close enough to get struck by lightning.

Two of the key ingredients for the drenching and damaging thunderstorms closing out this holiday weekend is the heat and humidity once again gripping the Northeast and sending temperatures soaring into the 90s along the I-95 corridor, northward to Portsmouth, N.H.

The heat will ease some on Monday, especially away from the I-95 corridor, but the air will still feel sticky to residents as higher humidity remains.