A powerful storm is about to dump an entire month’s worth of rain on the Northeast, forecasters warn. They expect the system to slow down and intensify as it moves into the region today, bringing a potentially significant flash flooding threat to multiple states.
The National Weather Service (NWS) has issued flood watches across wide swaths of New York, Pennsylvania, New Jersey, and southern New England. Forecasters expect repeated rounds of drenching thunderstorms to hammer parts of the region through Wednesday evening, particularly the tri-state area. The New York City metropolitan area can expect two to five inches (five to 13 centimeters) of rain over the next two days, with locally higher amounts possible.
Bryan Ramsey, a meteorologist at the New York City NWS office, told Gothamist that some of the flooding could be “potentially life-threatening,” as some storms could drop two to three inches (five to eight centimeters) of rain per hour.
“Even an inch an hour can cause minor flood issues in the New York City metro area,” he said, “so when you’re approaching two to three inches per hour, or at least potentially, that’s when you could start seeing some real flood issues.”
A slow-moving system will bring multiple rounds of heavy showers and thunderstorms today through Wednesday. There is potential for life threatening flash flooding. Isolated severe thunderstorms are possible, mainly for portions of northeast NJ and NYC. https://t.co/LpL4h0XYMs pic.twitter.com/mZUm0aq56V
— NWS New York NY (@NWSNewYorkNY) July 28, 2026
An unlikely summer storm
CNN meteorologists report that the storm’s strength will be more on par with systems typically seen in October, November, and December when it lingers over central New York on Wednesday. Although we associate summer with thunderstorms, storms generally don’t pack as much of a punch during this season because the jet stream is weaker and positioned farther north near the Canadian border.
This unusual system emerged from the same atmospheric disturbance that triggered severe thunderstorms in parts of the Great Lakes and Ohio Valley on Monday, as well as a destructive tornado in northeast Wisconsin, according to CNN. It is also drawing power and moisture from hot, humid air over the Southeast, where a scorching heat dome has been stubbornly in place for days.
While the Northeast will face the greatest flood threat, there is also a slight risk for the Mid-Atlantic and Ohio Valley, according to the NWS. In these regions, storms could also produce damaging winds, large hail, and a few tornadoes.
The dangers of flash flooding
Flash floods are one of the deadliest weather hazards in the U.S., according to the NWS. These events are so dangerous because they combine the destructive power of a flood with incredible speed. Urban and poorly drained areas are particularly prone to flash flooding as pavement and other hard surfaces prevent water from soaking into the ground.
The New York City Emergency Management Department has initiated the city’s Flash Flood Emergency Plan and has advised New Yorkers to allow for extra travel time during periods of thunderstorms and heavy rain.
“Heavier downpours could lead to localized flooding in poor drainage and low-lying areas, along with ‘potential scattered flooding’ on roadways, highways, and underpasses,” the department said in a statement, though it does not expect to see widespread flooding past Tuesday night.
Other major cities are facing a flash flood threat as well, including Boston, Massachusetts; Hartford, Connecticut; and Newark, New Jersey.
The storm should weaken and move out of the Northeast by Friday, though some scattered showers and storms could form in its wake, according to CNN. If the forecast proves accurate, we’ll be adding this storm to the long list of extreme weather events the U.S. has experienced this summer.
