NEW YORK (VINnews) — New York City officials late Sunday urged residents to prepare for heavy rain, thunderstorms and possible flash flooding overnight into Monday, warning that the most dangerous conditions are expected during the morning commute.

Mayor Zohran Mamdani said city agencies spent Sunday clearing catch basins, inspecting flood-prone neighborhoods, contacting residents in basement apartments and positioning emergency crews across the five boroughs ahead of the storm.

The National Weather Service has issued a flood watch through early Tuesday, forecasting 2 to 3 inches of rain across much of the city, with isolated areas possibly receiving up to 6 inches. Rainfall rates could reach 2 to 3 inches per hour, raising the risk of rapid flooding in low-lying and poorly drained areas.

Officials said the greatest flood threat is expected between 4 a.m. and 10 a.m. Monday, when heavy rain could inundate streets, underpasses and highways. Strong thunderstorms may also bring damaging wind gusts capable of downing tree limbs.

The city has activated its Flash Flood Emergency Plan, with the New York City Emergency Management coordinating preparations alongside city and state agencies, utilities and private-sector partners.

Specialized emergency crews, including the Downed Tree Task Force and Tow Truck Task Force, have been placed on standby. The New York City departments of Environmental Protection, Sanitation and Transportation spent Sunday clearing catch basins, while police prepared tow trucks for possible street flooding.

Officials urged residents to avoid unnecessary travel during periods of heavy rain, never drive or walk through floodwaters, and use public transit whenever possible. Those living in basement apartments or flood-prone areas were advised to have a plan to move to higher ground if flooding develops.