Storms Threaten to Bring Heavy Rain Across the Mid-Atlantic on Tuesday

Parts of the Mid-Atlantic States — including Pennsylvania, Maryland, Delaware, Virginia and New Jersey — were on alert on Tuesday evening, as a forecast for thunderstorms and heavy rain led to flash flood warnings across the region.

The severe weather caused delays at some of the busiest airports on the East Coast, including in Baltimore, Boston, Newark, New York City and Washington.

There were more than 300 flight cancellations and 1,100 delays Tuesday evening, many in the New York and Washington regions, according to the tracker FlightAware.

The National Weather Service said that thunderstorms would move from Northern Virginia up to New Jersey until 9 p.m. Eastern time, and warned of the possibility of damaging wind gusts up to 70 miles per hour.

Those storms could bring flash floods to Baltimore, Philadelphia and Lancaster, Pa., the Weather Service said.

In Toms River, N.J., a town on the Jersey Shore, the agency reported that one to 1.5 inches of rain had fallen, and that an additional 1.5 to 3 inches were possible. There were some road closures.

Some of the warnings on Tuesday were for areas that received significant amounts of rain the day before, resulting in what the Weather Service described as “widespread flash flooding.”

Much of Lancaster County received between two and four inches of rain on Monday night. Manheim, Pa., recorded approximately six inches, the service said.

The Weather Service warned that additional rain on Tuesday would fall on ground that was already heavily saturated.

About 60,000 utility customers in the region were without power on Tuesday evening, according to PowerOutage.us.