Torrential rain swept across New York City during Monday’s commute, triggering a flash flood warning as streets flooded in parts of Brooklyn and forecasters monitored the potential for further thunderstorms.
Rainfall rates could reach 2 inches (51 mm) per hour beneath the strongest downpours, fast enough to overwhelm storm drains and flood highways, underpasses and low-lying neighborhoods.
Around 1 inch (25 mm) of rain had already fallen by 7 a.m. on August 3. Although the first wave of heavy rain was expected to ease, city officials warned that the wider period of greatest concern would continue from 10 a.m. until 6 p.m.
☔️ NYC Inundated With Rain
— Citizen NYC (@CitizenAppNYC) August 3, 2026
Heavy rain has overwhelmed storm drains across the city. NYC Emergency Management is urging residents in basement apartments or flood-prone homes to identify their exits now and be ready to move to a higher floor before water arrives. pic.twitter.com/3gOfWltOBB
The flooding threat developed within a very humid and moisture-rich atmosphere over the New York metropolitan area.
When showers formed, they were able to draw on this deep supply of moisture and produce heavy rain within a short period. Rather than falling steadily throughout the day, much of the rain arrived in concentrated bursts.
This setup can create sharp differences in rainfall over relatively small distances. One neighborhood may receive only a brief shower, while another experiences a nearly stationary downpour capable of dropping more than an inch of rain within minutes.
The forecast rate of up to 2 inches (51 mm) per hour did not mean every part of the city would receive that amount. It represented the potential intensity beneath the strongest showers and thunderstorms.
Prepare for rain, #NYC. ☔@GuyBrownWeather says a Flash Flood Warning remains in effect until 8:45 a.m. The heaviest rain is expected during the morning commute and through the morning hours.
— NY1 Weather (@NY1weather) August 3, 2026
High temperatures will reach the low 80s. pic.twitter.com/sAHWBl90iU
Heavy rain produced significant flooding across parts of Brooklyn, with particularly dangerous driving conditions reported in Coney Island.
At Neptune Avenue and Ocean Parkway, floodwater rose close to the edges of the sidewalks, turning sections of the roadway into what resembled a narrow pool.
Vehicles moving through the flooded area sent waves toward nearby curbs. Drivers slowed sharply and took turns passing through deeper sections near a traffic light, waiting for oncoming vehicles to clear before proceeding.
Motorists described the conditions as stressful and warned that vehicles could stall or suffer damage if water entered the engine or electrical systems.
Even apparently shallow floodwater can conceal potholes, debris or sudden changes in road depth. City officials urged drivers not to enter flooded streets because conditions can become dangerous within minutes.
Dear @MTA, on today’s rainy commute I discovered your newest subway feature: indoor rain. Water was literally pouring from the ceiling of my Q line subway car. Pretty sure “weatherproof” isn’t supposed to be optional. CC: @NYCMayor @NYCComptroller @ZohranMamdani #nyc pic.twitter.com/qOpkXZpeC5
— Judy Rybak (@JudyRybak) August 3, 2026
A temporary reduction in rain was possible between the morning downpours and the next round of storms.
However, forecasters were monitoring the potential for a line of thunderstorms to cross the region during the afternoon and early evening. Any storms developing between approximately 3 p.m. and 7 p.m. could bring another burst of torrential rain, lightning and renewed disruption during the evening commute.
Where several storms pass repeatedly over the same neighborhoods, rainfall totals can rise rapidly. This process, known as training, occurs when cells move over the same location one after another.
Even short-lived thunderstorms can cause serious urban flooding when rain reaches the ground faster than the drainage system can remove it.
Why New York floods so quickly
New York City’s dense network of roads, sidewalks, buildings and other hard surfaces leaves relatively little exposed soil available to absorb heavy rainfall.
Water instead runs toward storm drains, subway entrances, underpasses and lower sections of the street network. Once drains become overwhelmed or blocked, water can begin pooling within minutes.
The risk is especially high in places such as Coney Island, where low-lying streets can allow water to accumulate quickly.
Highways and underpasses also present serious dangers. Water that appears shallow may be substantially deeper than expected, particularly during an intense downpour when visibility is poor.
Officials urged people living in basement apartments to move to a higher floor before water began entering their homes.
Below-ground rooms can flood rapidly, sometimes blocking doors, windows and other escape routes. Residents were advised not to wait until water was already rising before leaving.
New Yorkers were also encouraged to monitor emergency alerts, avoid flooded basements and limit unnecessary travel while warnings remained active.
Drivers should never attempt to cross a flooded roadway. Water can conceal road damage, move vehicles from their path or cause engines to fail before occupants have time to escape.
Monday’s downpours followed several other episodes of heavy summer rain across New York and the wider Northeast.
Warm-season air can carry large quantities of atmospheric moisture. When that humid air is lifted by a front, disturbance or thunderstorm boundary, it can release rain with remarkable efficiency.
The main threat remained localized flash flooding rather than continuous citywide rainfall. Conditions could improve quickly between storms, but any renewed downpour producing 1 to 2 inches (25 to 51 mm) per hour could turn streets into dangerous channels with little warning.
