- The fourth nor'easter in a month is set to dump a foot of snow from Philadelphia to Boston, the National Weather Service says.
- More than 3,300 flights had already been canceled at the three major airports that serve New York.
- All federal offices in the Washington metro area are closed for the day, the Office of Personnel Management announced early Wednesday morning.
Millions of commuters along the East Coast face another round of heavy snow, ice and wind gusts on Wednesday as the fourth major snow storm this month strikes the region, closing schools, grounding flights and halting buses and trains.
The nor'easter storm is on track to dump up between 12 and 18 inches of snow on areas from Philadelphia to New York City, said Weather Prediction Center meteorologist Dan Petersen. Gusts of up to 50 miles per hour are also expected to hit major cities on Wednesday and into Thursday, the National Weather Service said.
"Significant amounts of snow, sleet and ice will make travel very hazardous or impossible," the service said in an advisory for New Jersey.
More than 4,300 flights have already been cancelled. Airlines said they were waiving fees to change flights to and from the East Coast. Carriers including American, Delta, United and JetBlue said travelers scheduled to fly on Tuesday or Wednesday from a dozen airports along the East Coast can change travel dates to as late as March 25 without paying a date-change fee.
The storm forced schools across the region including those in Philadelphia and New York, the largest school district in the United States, to cancel classes on Wednesday.
But classes in New York City will resume on Thursday, according to the press secretary for New York City Mayor Bill de Blasio.
In New Jersey, Governor Phil Murphy on Tuesday declared a state of emergency, with state offices as well as schools in many districts closed.
The White House cancelled all public events for Wednesday, including a highly anticipated meeting between Facebook executives and members of the House Judiciary Committee, which was postponed until Thursday. The Office of Personnel Management announced early Wednesday morning that all federal offices in the Washington metro area are closed for the day.
Both Greyhound bus service and Amtrak passenger train service suspended or abbreviated routes for the day. Amtrak announced it will offer abbreviated service on Thursday, pending improvements in track conditions. Throughout the East Coast, local bus and train services that millions of people rely on to commute to and from work and school also cancelled service on Wednesday.
The Port Authority of New York and New Jersey suspended service after 3 p.m. in parts of New York City.
Widespread power outages were also expected on Wednesday as heavy snow and ice along winds may topple trees and power lines, the service said.
The New York City Housing Authority, home to close to 400,000 city residents, reported widespread power outages across their 326 developments. Power is expected to be restored by the end of the day for the 4,000 residents affected.
The East Coast storm, the fourth winter blast of snow and wind this month, was dubbed a "four'easter" by some news media outlets. It followed storms on March 2, 7 and 12 that left at least nine people dead across the region and more than 2 million homes and businesses without power.
– Reuters contributed to this report.