Why it matters: The threat comes amid recent severe weather, including tornadoes in Pennsylvania and damaging storms in other regions.

What to do: Residents should secure outdoor items, monitor alerts, and have shelter plans ready as storms approach.

Severe weather alert issued for millions across eastern U.S.

The Storm Prediction Center has placed parts of Pennsylvania, Maryland and Virginia under an Enhanced Risk for severe weather on Tuesday, with a lower but still significant threat extending into New York, New Jersey, Connecticut and Massachusetts. Forecast models show numerous severe thunderstorms developing along a strong cold front, producing damaging wind gusts up to 75 mph, large hail, flash flooding, and isolated tornadoes. The most dangerous period is expected from Tuesday afternoon into nighttime, with storms shifting south and east by Wednesday.

Why today's storms could hit harder

Meteorologists warn that the combination of warm, humid air and a strong cold front will fuel intense instability, supporting supercells and bowing thunderstorm lines capable of widespread wind damage. While damaging winds are the primary hazard, embedded supercells near the surface low could produce large hail and a couple of tornadoes. The setup is consistent with other severe weather patterns that have caused widespread damage.

Communities still reeling from July 18 tornadoes

Storms on Saturday led to four confirmed tornadoes in Pennsylvania, including EF-0 tornadoes in Westmoreland and Jefferson counties and an EF-1 in Clarion County. In Westmoreland County, a tornado passed near homes and businesses, downing trees and causing flooding that damaged roads and bridges. Crews are continuing cleanup and infrastructure repairs while monitoring forecasts for more storms.

"I lost my appetite. I mean it was right around dinner time, and I couldn't eat; my heart was pounding. I mean literally I was just hoping for the best. I was very lucky. Very lucky. Some trees were down on the tree line, but all the greenhouses were untouched. All of the mums I had in the parking lot were untouched too, so very lucky."

Colin McChesney