Nor’easter Map: NYC, Boston, Long Island Face Major Coastal Flooding Threat

A strengthening early-season nor’easter is moving north along the East Coast on Friday, September 25, bringing coastal flooding, pounding surf, strong winds and heavy rain from North Carolina to New England, according to the National Weather Service.

The storm is expected to intensify through Saturday before gradually weakening Sunday, although rain and gusty winds could continue into Monday.

More than 40 million people could be affected through the weekend. New York City, Long Island and Boston are among the areas facing the most significant combination of wind, rain and high-tide flooding, while parts of coastal New England could receive up to 5 inches of rain.

Why the coast is facing repeated flooding

The storm is arriving while water levels are already elevated along parts of the East Coast. Persistent winds are pushing ocean and bay water toward the shoreline, while the full moon Saturday is raising high-tide levels.

That combination means flooding can occur during several high tides instead of being limited to one event. The Weather Channel said the most significant coastal flooding is expected from the northern Outer Banks of North Carolina through southern New Jersey, including the Virginia Tidewater, Chesapeake Bay, and Delaware Bay.

The effects are already being seen. A 16-mile section of North Carolina Highway 12 on the Outer Banks has been closed in both directions because ocean water washed across the road. Rising water also led to the cancellation of the Oceans Calling festival in Maryland.

What happens in New York and Boston

New York City is expected to see periods of heavy rain and strong winds, particularly from Friday into Saturday. Coastal flooding could become worse when heavy rain arrives around high tide, creating a risk for low-lying parts of the city.

Boston and other parts of coastal New England face stronger conditions as the storm moves north. Wind gusts could reach 60 mph in parts of eastern Long Island and coastal New England, with the strongest conditions expected Friday and Saturday. The winds could damage trees and cause scattered power outages.

The heaviest rainfall is expected across coastal New England. Urban areas, including the Boston metropolitan area, could experience flash flooding, while eastern Long Island is expected to receive more rain than areas farther west around New York City.

New York City Mayor Zohran Mamdani issued a travel advisory Friday as the storm’s projected path moved closer to the city. “The forecast path of this storm has moved closer to our city, and it is bringing more rain and stronger winds with it,” Mamdani said.

Nor’easter timeline through Monday

The storm’s strongest impacts will develop over the next several days.

Friday: Heavy rain, stronger winds and coastal flooding spread into southeastern New England. Long Island could see flooding during high tide, while gusty winds continue farther south along the coast.

Saturday: The storm reaches a key period of impact, with strong winds and locally heavy rain across coastal New England. Rain is expected in New York City, while high-tide flooding could affect areas from New England to parts of the Mid-Atlantic.

Sunday: The nor’easter should weaken, but showers and gusty winds could remain across parts of New England and the Hudson Valley.

Monday: Remaining showers should gradually move out of the Northeast.

Travel and beach risks remain

The storm could create problems for both road and air travel. Boston Logan International Airport faces a higher chance of delays, while delays are also possible at New York City’s three major airports. Downed trees, flash flooding, and dangerous conditions near the coast could affect roads.

People near the shoreline also face dangerous surf and beach erosion. Repeated high tides and pounding waves could worsen erosion along exposed beaches through the weekend.

The weather is also affecting events. The Oceans Calling festival in Maryland canceled its first day because of weather conditions and beach erosion. Organizers said, “The safety of our fans, artists, crew, and community must come first.”