Meteorologist Amy Freeze says there could be drenching downpours Monday afternoon north and west of New York City before skies begin to clear on Tuesday.
As rain continued falling on Sunday, the water was as high as car bumpers in some spots, trapping drivers inside their cars.
Video posted on social media showed severe flooding in parts of New Jersey.
Paterson (Union Avenue):
Some areas received 4 to 6 inches of rain over a 24-hour period from Saturday to Sunday.
A flash flood watch is in effect through Monday night for Monmouth, Hunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and Warren counties.
Forecasters say the potential exists for some locations to receive 1 to 2 inches of new rainfall in less than an hour.
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