Most of New Jersey and areas west of Philadelphia are expected to see about 2 inches of rain between Sunday, July 9 and Tuesday, July 11, AccuWeather reports.
The Poconos, North Western New Jersey and the Lehigh Valley could see up to four inches of rain.
Storms were expected to begin in North Jersey in the evening hours, and remain strong through Monday, July 10, forecasters say.
A severe thunderstorm watch was also issued for much of New Jersey as of Sunday afternoon, as storms were already under way in parts of South and Central Jersey, as of 3 p.m.
Parts of eastern Pennsylvania were already flooding as of noon on Sunday, with between two and four inches of rain having already fallen, AccuWeather says.
A flood warning was issued across Central Pennsylvania, with things looking particularly bad in Dauphin and Cumberland counties.
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