The watch includes Westchester, Putnam and Rockland as well as Orange County, New York City, Staten Island and Long Island.
There is the potential for damaging wind gusts late Wednesday evening into overnight with a line of rain and thunderstorms ahead of a cold front that is due to arrive Thursday.
Localized flooding is also possible in areas of poor drainage as well as streams and small rivers.
By the time the system wraps up Thursday morning, the area could see up to 2 inches of rainfall.
The outlook for Thursday calls for cloudy skies with temperatures falling during the afternoon to the low 40s as the cold front arrives.
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