Flash flood threat continues across New England, targets Mid-Atlantic after inundating New York tri-state

( Yahoo )

Millions across New England, the Mid-Atlantic and parts of the Appalachians are under a flash flood threat Tuesday as a slow-moving front continues to sag south after inundating parts of New Jersey, Pennsylvania, Coastal Connecticut, Rhode Island and the New York City metro area on Monday.

Torrential downpours flooded neighborhoods and roads and even caused a roof collapse at a wholesale club in Monmouth County, New Jersey.

Authorities said the collapse happened at around 11:15 a.m. There were 27 people inside the building at the time.

Two individuals were partially trapped, but were able to free themselves and safely get out of the building, according to the sheriff's office.

Heavy rain flooded communities along the Jersey shore. Drone video shows neighborhoods bad subdivisions in Deal and Asbury Park completely inundated.

Flash flooding inundated parts of New York's Long Island, where drivers navigated flooded roads to leave their neighborhoods and some vehicles became stranded in high water.

Danbury, Connecticut has tallied more than 6 inches of rain since Sunday.

The widespread flash flooding was triggered by a low-pressure system that moved onshore and ended an oppressive, deadly heat wave over the July 4 holiday.

On Tuesday, a slow-moving weather system stretching from Ohio to northern Virginia will bring more rounds of rain, with the heaviest concentration likely over an area from southern Pennsylvania into Virginia, where flood watches remain in effect.

NOAA's Weather Prediction Center has issued a Level 2 out of 4 flash flood threat for this area through Wednesday morning.

Farther south, thunderstorms are expected to develop Tuesday afternoon across the Mid-Atlantic and Carolinas, with damaging wind gusts as the primary hazard.

These storms could also increase the flash flood risk for parts far eastern West Virginia and Virginia.

Meanwhile, another area of low pressure is tracking into Boston and Providence, Rhode Island, where a Level 1 flash flood threat is in effect.

The heaviest rainfall is expected through mid-morning before showers gradually diminish during the afternoon.

Localized rain totals exceeding 3 inches are possible across Plymouth, Barnstable, and Bristol counties in Massachusetts.

Severe storms battered the region across the July 4 holiday weekend, beginning late Friday afternoon, leading to the cancellation of some outdoor celebrations.

Powerful wind gusts took down trees and power lines, with more than 280,000 customers still without power early Monday.

Heavy rain Sunday prompted New York City Mayor Zohran Mamdani to warn people living in basement apartments to be ready to evacuate. The city opened public schools to serve as shelters late Sunday.