Children across parts of the northeastern United States will stay home on Monday as a powerful winter storm forced school closures and pushed offices and transit systems onto emergency schedules, with officials across the region warning of heavy snow, strong winds and dangerous travel conditions.

New York City Mayor Zohran Mamdani declared a state of emergency and ordered non-essential vehicles off city roads from Sunday night to noon Monday, saying plows and emergency crews needed the streets clear as snowfall intensified.

The city is under its first blizzard warning since 2017.

City offices will close for in-person services, and non-essential municipal employees may work remotely. “I’m urging every New Yorker to please stay home,” Mamdani said.

New York City, the nation’s largest school district, ordered all public school buildings closed for a traditional snow day, with no remote instruction and all after-school programs cancelled.

The storm has already snarled travel along the East Coast from Washington to New England, with airlines canceling thousands of flights and officials urging people to stay off the roads.

Winter weather in the Northeast may also slow the processing, transport and delivery of mail and packages, the US Postal Service said.

Regional emergencies

New York Governor Kathy Hochul said she had activated 100 National Guard members to assist in Long Island, New York City and the Lower Hudson Valley — areas expected to bear the brunt of the heavy snow and coastal winds.

The storm also forced closure of the United Nations (UN) headquarters complex in Manhattan on Monday.

Parts of the Northeast could see up to two feet of snow and wind gusts could reach 70 mph, raising the risk of falling trees and power outages, according to the Department of Homeland Security (DHS).

In an update on Sunday, the agency said despite its ongoing funding lapse, the Federal Emergency Management Agency’s (Fema) disaster‑response work continues uninterrupted, including staff travel, emergency operations, and critical assistance for people affected by active disasters, with life safety and property protection remaining top priorities.

Last week, Reuters reported that US President Donald Trump’s administration had ordered Fema to suspend the deployment of hundreds of aid workers to disaster-affected areas around the country while the DHS is shut down.

Massachusetts Governor Maura Healey declared an emergency and told state workers to stay home. Connecticut barred commercial vehicles from limited-access highways Sunday evening, exempting only emergency and essential deliveries.

New Jersey Governor Mikie Sherrill declared a statewide emergency effective noon Sunday and urged residents to take the storm seriously. “People need to take this very seriously,” she told CNN.

Travel disruptions

Air travel was among the earliest casualties. Flight-tracking site FlightAware showed more than 5,000 flights already canceled for Monday.

Aviation analytics firm Cirium said more than 25,000 flights were scheduled to depart from the United States on Monday, with cancellations also rising for Tuesday, especially at major Northeast airports.

NJ TRANSIT suspended bus, light rail and Access Link service Sunday evening and halted statewide rail service by Sunday night, with operations resuming only when conditions allow.

In New England, the Rhode Island Public Transit Authority said it would suspend all service — including its RIde paratransit program — from Sunday night through Monday and would announce plans to resume service only when conditions improve.