Washington will need several more days to return to normal after a weekend blizzard dropped more than 60cm of snow along the US East Coast, killing more than 30, and likely causing billions of dollars in damage.
The nation's capital was at a standstill, with federal government offices ordered shut on Monday (local time), schools in the district and surrounding suburbs shuttered and the US House of Representatives cancelling all votes until next week.
Washington Mayor Muriel Bowser said public schools would remain closed on Tuesday but city government offices would reopen. She urged people to use mass transit rather than trying to drive and park on the city's snow-clogged roads.
"We knew that we would have... several days of clean-up ahead of us," Bowser told reporters. "Know that we're going to be dealing with snow all of this week."
Officials reported at least 36 storm-related deaths, including traffic accidents and heart attacks while shovelling in Washington, Delaware, Kentucky, Maryland, New Jersey, New York, North Carolina, South Carolina, Ohio, Tennessee and Virginia.
The dead included a North Carolina man who was shot and killed when he saw a motorist who had run off the road in the storm and attempted to help him. The motorist remained jailed on murder charges on Monday.
The storm likely caused billions of dollars in economic losses, including damage to buildings and lost business from closures, reinsurance broker Aon Benfield said on Monday.
Officials said that all but one line on Washington's second-busiest subway system would resume service on Tuesday.
High snowbanks at street corners made travel within Washington difficult for pedestrians.
Even with federal government offices officially closed, the Supreme Court was open for business, scheduled to issue rulings and act on pending appeals from the snowbound courthouse across from the US Capitol building.
Washington officials said the city has applied for federal disaster relief to help pay for the snowstorm's costs, which they did not estimate.
Ten public schools around the city opened to provide breakfast and lunch to low-income children who typically receive free meals at school, officials said.
Air travel remained seriously affected as about 1603 US flights were cancelled on Monday, with Newark Liberty International Airport, New York's LaGuardia Airport and Washington Dulles International Airport the hardest hit, according to FlightAware.com.
"This has been a nightmare," said Mary Lavigne, 34, as she waited at LaGuardia with her 18-month-old daughter for a flight to Montreal.
"We've come to the airport twice, only to have to go back home... The trip is proving as brutal as the storm."
New York was quicker to return to business, with the New York Stock Exchange and the city's public schools open.
New York City Mayor Bill de Blasio told a local radio station he thought the city would face more storms of this magnitude in the future.
"We're now in the age of extreme weather. You know, this is what climate change has done to us. These storms are much bigger than what we've seen in the past," de Blasio said. "The mega storm is going to be with us for a while now."
Along New Jersey's southern coast, business owners were left to mop up the damage of a storm surge that flooded homes and businesses in the popular tourist area.
Several expressed frustration with Governor Chris Christie's weekend comments that the area hit by this storm had not borne the brunt of 2012's Superstorm Sandy.