The National Weather Service's Doppler radar was tracking strong thunderstorms moving east at 35 mph toward Westchester County at that time, its website said.
Frequent cloud to ground lightning was predicted with winds of up to 40 mph, the weather service warned.
Lightning is one of nature's No. 1 killers, the weather service said. If you can hear thunder, you are close enough to be struck by lightning and should move to safe shelter immediately.
Showers and thunderstorms were expected mainly before 3 a.m. Saturday, the weather service said. Some of the storms could produce heavy rain, and the temperature should drop to about 48 degrees.
Saturday will open mostly cloudy, then gradually become sunny, with a high near 57.
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