Thunderstorms are expected to roll through Delaware late Saturday afternoon or early evening, with a severe thunderstorm watch in effect until 9 p.m.

A heat advisory is also in effect until 8 p.m. and a flood watch is in effect until midnight.

The late-afternoon or early-evening storms come as the weather officials predicted heat index values up to 101 on Saturday. This week, Delaware and neighboring states have been in their fourth heat wave of the summer.

Severe thunderstorms could bring high winds

The severe thunderstorm watch includes many states along the East Coast, including Virginia, Maryland, Delaware, New Jersey, Pennsylvania, New York, Connecticut and Washington, D.C.

National Weather Service officials say “scattered gusts” up to 70 mph are likely.

Frequent lightning and hail are also possible.

Flash flooding also possible

Saturday evening’s thunderstorms are predicted to bring patches of heavy rain, which could lead to localized flash flooding.

The National Weather Service said some areas could get multiple rounds of storms, “increasing the potential for flash flooding, especially in urban areas and other areas with poor drainage.”

Though the rain may linger past midnight, overnight storms “aren’t expected to have as much potential for heavy rainfall,” a weather alert said.

Will Delaware be affected by tropical storm?

It’s unclear whether a tropical depression that’s expected to strengthen into a tropical storm later on Saturday and likely hit Florida will affect Delaware.

The National Weather Service predicts some rain toward the middle and end of this week, though it’s certainly not guaranteed.

The agency’s Mount Holly, New Jersey, office said Saturday morning that it was keeping an eye on the storm.

“Local impacts may not begin to occur until late next week,” a post on X said.

Atlantic storm tracker

Atlantic storm spaghetti models

Illustrations include an array of forecast tools and models, and not all are created equal. The National Hurricane Center uses only the top four or five highest performing models to help make its forecasts.

Contributing: USA TODAY

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