Radar shows the storms heading through Rockland County and into Westchester then Fairfield County, the weather service said. Heavy rain and thunderstorms were possible after 7:15 p.m.
Torrential rains and flash flooding were associated with the storm, which was heading east at 50 mph. Gusts of up to 50 mph were possible.
Residents in southern Fairfield County were warned, especially in Bridgeport, Stamford, Norwalk, Shelton, New Canaan, Fairfield, Greenwich, Stratford, Trumbull, Redding, Westport, Wilton, Weston and Darien.
The storm could cause localized flooding low-lying and poor drainage areas. Drivers are reminded to not drive cars through flooding on local roads.
Rain and fog will continue into Sunday night. But Monday will be mostly sunny with a high near 80.
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