(Adds emergency declared for New York City)
NEW YORK, March 21 (Reuters) - The U.S. East's fourth major snowstorm this month swept through the region with heavy snow and high winds on Wednesday, snarling flights and commuter travel, closing schools and triggering emergency declarations in New York City and New Jersey.
The nor'easter was on track to dump 12 to 18 inches (30 to 46 cm) of snow on areas from Philadelphia to New York City on Wednesday, said Weather Prediction Center meteorologist Dan Petersen.
The storm also lashed points along the East Coast with winds exceeding 50 miles (80 km) per hour, according to the Weather Prediction Center.
The wintry blast on the second day of spring was dubbed "four'easter" by some media outlets because it struck after three previous storms this month. Those nor'easters left nine dead and more than 2 million homes and businesses without power.
New York state Governor Andrew Cuomo declared local emergencies for New York City, where several inches of snow had fallen by Wednesday afternoon, and some other parts of the state.
"The roads are very icy and the roads are dangerous and there is no reason to be on the roads unless it's an emergency," Cuomo told a news conference. "The storm will get worse before it gets better."
The snowfall in the Northeast is not expected to wane until Thursday, Weather Prediction Center meteorologist Frank Pereira said in a phone interview.
In New Jersey, Governor Phil Murphy on Tuesday declared a state of emergency, as crews cleared roadways. Transit bus service was ordered suspended statewide starting Wednesday afternoon.
Throughout the East Coast, many other buses and trains, including some Greyhound bus and Amtrak rail routes, that millions of people rely on to commute to and from work and school also canceled service on Wednesday.
With many commuters staying home, New York City's normally bustling Times Square was sedate.
"We're not going to let the snow get in the way of our snow day," said Cheryl Mandelbaum, 30, an elementary school teacher who was taking pictures with a friend, another teacher who had the day off because the city had canceled school.
Several inches of snowfall in Washington and its suburbs forced the closure of federal government offices, according to the U.S. Office of Personnel Management.
Washington schools were also closed, and children in Philadelphia, parts of New Jersey and Pittsburgh also enjoyed a snow day. In Boston, students were told to trudge to school.
The storm dumped about a foot (30 cm) of snow on parts of Maryland and Pennsylvania, according to the National Weather Service, while further inland snow also blanketed parts of Ohio, Indiana and Kentucky.
Airlines scrapped more than 4,412 flights into and out of the United States, according to flight tracking website FlightAware, and more than 2,000 other flights were delayed.
The nor'easter caused some power outages, but the region escaped the widespread blackouts of past snowstorms. About 12,000 homes and businesses lost power in Maryland, and thousands of others lost power in Virginia, West Virginia and New Jersey.
Across the country in Southern California, residents of Santa Barbara County braced for potential mudslides as rains hit the region. (Additional reporting by Alana Wise and Scott DiSavino in New York, Bernadette Baum in Montclair, New Jersey, Suzannah Gonzales in Chicago, Keith Coffman in Denver, and Brendan O'Brien in Milwaukee; Writing and additional reporting by Alex Dobuzinskis, Editing by Jonathan Oatis)