WESTFIELD, NJ — The National Weather Service issued a severe thunderstorm warning for Union and Essex counties Monday afternoon but the warning expired within an hour when the storm did not materialize as initially expected.

The thunderstorm, spotted in Middlesex County at 4:35 p.m. and moving at 25 mph, was anticipated to damage trees and power lines in northern New Jersey, the Weather Service warning issued Monday said.

Winds of up to 40 mph remain possible, the Weather Service said shortly after 5 p.m.

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"We expect heavy rains from Tropical Depression Florence but the Town of Westfield is prepared," said Acting Westfield Police Chief Chris Battiloro.

Track power outages on the PSE&G outage map.

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