Weather Alert Issued For NYC As Heavy Rain and Thunderstorms Threaten Thursday
New York City Emergency Management (NYCEM) has issued a Weather Alert for Thursday, August 20. According to the National Weather Service (NWS), showers and thunderstorms are expected to move through the area Thursday afternoon and evening, with locally heavy downpours that could produce isolated to scattered flash flooding.
Scattered showers are expected to begin late Thursday morning, with the bulk of the widespread showers and embedded thunderstorms expected between approximately 2 p.m. and 8 p.m. The heaviest rainfall is currently expected between 5 p.m. and 8 p.m., which could affect the evening commute. NYCEM has activated the City’s Flash Flood Emergency Plan and is coordinating with the NWS and City agencies to monitor conditions and prepare for potential impacts.
The NWS Weather Prediction Center has placed New York City in a Slight Risk (Level 2 of 4) for excessive rainfall on Thursday. This carries the potential for isolated to scattered flash flooding.
Current forecasts call for approximately 0.75 inches to just over 1 inch of rain across New York City, with higher totals possible in localized areas. Higher rainfall amounts are currently more likely across southern portions of the city.
Brief rainfall rates of 1 to 2 inches per hour are possible in stronger thunderstorms. However, the showers and thunderstorms are expected to move steadily through the area rather than repeatedly pass over the same locations, limiting the duration of the heaviest rainfall.
Localized rainfall totals of approximately 1.5 to 1.75 inches are possible in areas that receive heavier downpours. Higher amounts cannot be ruled out in a low-probability scenario.
The greatest risk for heavy rainfall and localized flash flooding is expected during the late afternoon and evening, including the evening commute. Showers and thunderstorms should begin to taper off after approximately 8 p.m., with generally dry conditions expected after midnight Thursday night into Friday morning.