(Adds comments from authorities, details on weekend forecast)
By Scott Malone and Victoria Cavaliere
BOSTON/NEW YORK Jan 3 People across the northeastern United States on Friday dug out after a heavy snowfall that grounded flights, closed schools and government offices, caused at least three deaths and left the region in the grip of dangerously low temperatures.
Boston was hard-hit by the first major winter storm of 2014, getting nearly 18 inches (45 cm) of snow, while some towns north of New England's largest city saw close to 2 feet (60 cm) of accumulation.
Major cities from Washington, D.C., to Portland, Maine, were slammed, with New York's Manhattan island getting 6 inches (15 cm) of snow and parts of the borough of Queens seeing more than 10 inches (26 cm) of fresh powder.
While plows made easy work of the powdery snow to clear roads and runways, authorities warned residents to expect unusually cold weather across the Midwest and Northeast.
Embarrass, Minnesota notched a reading of -36 degrees Fahrenheit (-38 Celsius) that stood as the lowest temperature recorded in the United States outside Alaska on Friday, according to the National Weather Service.
"Temperatures tonight and tomorrow are expected to be extremely low, and dangerously so," said Massachusetts Governor Deval Patrick. "These are dangerous conditions."
The forecast overnight low for Boston was -4 F (-20 C) while New York looked for a low of 3 F (-16 C).
New York City's Department of Homeless Services went to "code blue," doubling the number of vans patrolling streets to seek people who needed shelter and streamlining the check-in process for homeless shelters.
Washington received more than 2 inches (5 cm) of snow, Philadelphia roughly 5 inches (13 cm) and Hartford 7 inches (18 cm). link.reuters.com/zym75v
In Cambridge, Massachusetts, just outside Boston, Tom Klein took a break from shoveling and said that a life in New England had accustomed him to harsh winter weather.
"I love a good snowstorm," the 60-year-old co-owner of a small manufacturing company said. "I don't mind shoveling. I've never minded shoveling."
Some 2,452 U.S. flights were canceled and 4,012 were delayed on Friday, according to FlightAware.com, which tracks air traffic.
Airports across the region warned travelers to expect residual delays as they cleared a backlog of flights.
"We now have all our airfields - runways and taxiways - clear," said Ed Freni, aviation director for Boston's Logan International Airport. "We will be back to normal operations by tomorrow."
The weather was a factor in at least three deaths.
In Kentucky, a 50-year-old woman died on Thursday morning when she lost control of her car on an icy road near South Williamson, according to state police.
Police recovered the body of a 71-year-old woman suffering from Alzheimer's disease who had wandered out in the rural western New York State town of Byron on Thursday night, improperly dressed for the single-digit temperatures, according to the Genesee County Sheriff's Office.
A Philadelphia city worker was killed after a machine he was using was crushed by a mound of rock salt, media said.
New York's new mayor, Bill de Blasio, started his day shoveling the walk in front of his Brooklyn brownstone - a task his wife had said their 16-year-old son Dante would handle.
Dante turned up later, not being an early riser, his father said at a briefing.
Asked what grade he would give his teen-aged son, de Blasio said: "I give Dante an A for effort and a D for punctuality."
De Blasio, who has pledged to address issues of inequality in New York, focused on the plight of homeless people during his weather briefings, saying city agencies stepped up outreach efforts to get needy people off the streets and into shelter during the dire cold.
He urged New Yorkers to keep an eye out for people who might be in danger and to contact city authorities if need be.
In Washington, the Office of Personnel Management told hundreds of thousands of federal workers they could work from home or take a leave because of the storm. The United Nations in New York and federal courts in New York, New Jersey, and Boston shut down. Schools closed across much of the region.
Not all New Yorkers had the option of staying home.
"The rent is too high. I can't close because of a storm," said Nelson Martinez, who was working at his Brooklyn grocery store, packing ice-melting salt from large bags into smaller sizes to sell.
"I'm just trying to make some extra money off it and turn a bad situation around," he said.
The Midwest braced for a bitter cold stretch from the weekend into early next week, as well as blizzard conditions in North Dakota and parts of South Dakota and Minnesota.
Minnesota Governor Mark Dayton on Friday ordered all public schools statewide to close on Monday due to the forecast extreme low temperatures. It will be the first time Minnesota public schools will be closed statewide since January 1997.
Forecasters called for a low of -26 degrees F (-32 C) in Minneapolis on Sunday night and a Monday high of -17 F (-27 C).
A possible winter storm was headed to the Ohio River Valley, including Indiana, on Sunday, with Detroit also facing a possible foot (30 cm) of snowfall. (Additional reporting by Ellen Wulfhorst and Barbara Goldberg in New York, Daniel Lovering in Cambridge, Massachusetts, Jeffrey B. Roth in Gettysburg, Pennsylvania, Kevin Murphy in Kansas City, Missouri, Dave Warner in Philadelphia, Mary Wisniewski in Chicago, David Bailey in Minneapolis and Ian Simpson in Washington; Editing by Jonathan Oatis)