Damaging thunderstorms and downpours will rip through part of the northeastern United States into Monday evening.
A press of cooler air will clash with building warmth and humidity over the mid-Atlantic and interior Northeast to start the month of May.
Residual showers and thunderstorms from the overnight and morning hours will intensify as they approach the central and southern Appalachians later in the day.
“Severe thunderstorms will develop this afternoon in western portions of New York, Pennsylvania, West Virginia and Maryland,” AccuWeather Storm Warning Meteorologist Joseph Bauer said.
The severe weather could extend as far north as southeastern Ontario, including Toronto and Ottawa.
These thunderstorms will then move eastward into the evening, surging into central and eastern Pennsylvania and central New York.
Wind gusts to 70 mph, local flash flooding and even a few tornadoes will be the concerns in this area, according to Bauer.
Tree and power-line damage is likely, along with sporadic power outages. Hail can also occur and cause further damage to buildings or cars.
“The threat will be greatest along the Interstate 79 and I-81 corridors,” AccuWeather Senior Meteorologist Kristina Pydynowski said.
Locally gusty thunderstorms could stretch as far south as the Carolinas, Georgia and northern Florida. Any severe weather will be fairly isolated along this corridor.
Cities at risk for the violent thunderstorms include Morgantown, West Virginia; Harrisonburg, Virginia; Pittsburgh and Harrisburg, Pennsylvania; and Buffalo, Syracuse and Binghamton, New York.
Residents who are enjoying the warmth and sunshine prior to the thunderstorms by taking part in warm weather activities should be prepared to seek shelter indoors at the first sight of lightning or clap of thunder.
The greatest severe hazards are expected to diminish as the thunderstorms approach the I-95 corridor from Washington, D.C., to New York City on Monday night. A heavy burst of rain and rumbles of thunder may rudely awaken residents along this swath.
“The passage of this front will slash highs by 10 to 20 degrees Fahrenheit around the eastern Great Lakes for Tuesday,” Pydynowski said.
Blustery conditions will accompany the cooler air, with winds gusting past 30 mph at times. Wind gusts whipping as high as 60 mph are possible over the Appalachians.
Further cooling will take place at midweek to the mid-Atlantic and New England coasts.
Umbrellas and rain jackets will be needed into late week, as a storm rides up the Eastern Seaboard and delivers a thorough soaking on Thursday and Friday.