The warning covers the five boroughs, Bergen, Essex, Hudson and Union counties in New Jersey and Nassau County on Long Island and southern Westchester County. The highest flash flood risk is along the I-95 urban corridor.
The New York City Emergency Management Department warned that the rain will cause flooding of highways and streets.
“Do not drive or walk where water covers the roadway. Move to higher ground, or, if in a basement, move to a higher floor,” the agency said in a tweet.
The storms have moved through the city and shifted eastward, the National Weather Service said, adding that the risk for additional storms may return.
A warning of severe thunderstorm – which could bring strong winds, hail, and even a tornado – was also issued for the city along with Northeast New Jersey. The storms could result in a slight drop in temperature, breaking the heatwave.
A few locations could top the 90-degree mark again, however, temperatures will drop to seasonable levels Tuesday. The New York City region witnessed the hottest and longest heat wave in a long time.
Coastal New Jersey could see the worst of the storms from 6 p.m. to 9 p.m., weather experts said. Newark, New Jersey, had hit 102 degrees Sunday. It was the fifth day in a row. Experts say that it also marks the longest stretch of days at 100 or higher in the city’s recorded history.
About 15,000 were without power by mid-afternoon Monday. The vast majority were Central Hudson customers.
In New York City, one person – with some underlying health conditions – died of heat-related exposure. The death is the first locally known to be connected to this excessive hight temperature, officials said.