It is in effect from 4 p.m. Sunday to noon Monday.
The watch also includes Putnam, Orange, Westchester and Rockland counties as well as southern Connecticut, northeast New Jersey, New York City and Long Island.
A Flash Flood Watch means that conditions may develop that lead to flash flooding, a very dangerous situation, the National Weather Service said in a statement, noting residents should monitor later forecasts and be prepared to take action should flash flood warnings be issued.
The storm could dump as much as 4 inches of rainfall.
After a sunny day Saturday, the storm bringing heavy rain and gusty winds will move through the tristate region starting early Sunday morning, with showers and possibly a thunderstorm after midnight, and overnight rainfall of a half-inch possible.
A stormy Sunday, the fifth anniversary of Super Storm Sandy, will see showers and thunderstorms, with some of the storms producing heavy rain, with rainfall amounts of up to 2 inches possible during daylight hours.
Gusty winds of up to 28 miles per hour could bring down trees and cause power outages and be accompanied by flash flooding and locally severe storms.
Rain, which will be heavy at times, will continue Sunday night with another 1 to 2 inches possible.
Spotty showers will continue until around noontime Monday as the cold front passes through, bringing down temperatures. Monday's high will only be in the mid- to upper-50s with partly sunny skies in the afternoon,
Check back to Daily Voice for updates on the storm.
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