It's in effect until 8 p.m. Thursday, Aug. 27, the National Weather Service said. It was issued just before 3:30 p.m. Thursday.
It covers Westchester, Putnam, Rockland and Orange counties in the Hudson Valley, Suffolk County on Long Island and Fairfield County in Connecticut.
The watch comes as a new round of severe storms is expected to sweep through the area. The main threats, including the potential for tornadoes, are damaging wind gusts up to 70 mph, golf-ball size hail, brief heavy downpours and local flash flooding.
The storms are expected through around about 10 p.m. Thursday.
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