"Don't lift with your back, lift with your knees," he advised as he dug into the sidewalk outside his Park Slope row house. Later, his teenage son emerged to help, prompting de Blasio to jokingly give him "an A for effort but a D for punctuality."
Faced with the first test of his leadership barely two days after taking the oath, de Blasio responded with a display of regular-guy charm — and a remarkably effective piece of political stagecraft — that would have been unimaginable for his predecessor, billionaire Michael Bloomberg.
"I've lived in New York for 70 years, and I can't recall a mayor shoveling before," said Kenneth Sherrill, a retired political science professor at Hunter College. "Several of them would have ended up in the emergency room if they tried."
After 12 years of the businesslike, buttoned-down style of Bloomberg, the storm offered a glimpse of a new style of leader in de Blasio, apart from their clear political differences.
De Blasio spoke of heading a conference call on the storm at 4 a.m. He faced the media in baggy blue jeans. And when asked by a reporter how many layers he was wearing in the 10-degree weather, he unzipped his jacket in a mock strip tease. "You want me to go farther?"
During the mayoral campaign, de Blasio's opponents frequently leveled the charge that he had little experience managing a large organization. He had a small staff as a city councilman, and as public advocate, he oversaw a $2 million annual budget. By comparison, New York City's annual budget is more than $70 billion.
In a sense, the storm provided an early opportunity for de Blasio to demonstrate his management mettle.
De Blasio put 1,700 plows on the streets soon after the snow started falling Thursday night. He acted early Friday to close schools, out of concern over bitterly low temperatures. And by late Friday morning, he announced that every one of the city's primary roads and nearly all of the secondary roads had been plowed.
Asked to grade his first test, he said: "Based on the information I have right now, I give everyone an A for extraordinary effort and extraordinary effectiveness."
Even before he was sworn in on Wednesday, de Blasio said he was keenly aware of the political dangers presented by snowstorms.
In 1969, John Lindsay's administration left Queens unplowed for days, trapping residents on their blocks. When Lindsay finally visited, his limousine got stuck in the snow and the mayor was berated by angry residents.
And just after Christmas 2010, a blizzard dumped more than 20 inches of snow on the five boroughs, but Bloomberg was nowhere to be found for hours. And then, after racing back from Bermuda on his private plane, he appeared out of touch to many by suggesting New Yorkers "go see a Broadway show," a suggestion that infuriated those still trapped in their homes and those with scant discretionary income.
De Blasio, drawing contrasts with the billionaire mayor, often dovetailed his criticism of the storm response with his own experiences as a homeowner, frustrations he shared again the day before his Wednesday inauguration as it was clear the new storm would slam the city.
"I remember that my own block didn't get cleared for three days," he said. "Something like a snowstorm, I take very personally. I can see it, I can feel it, I can touch it. It's not an abstraction."
But he denied that his previous criticisms upped the pressure on his own performance.
"I don't feel we have to get this right because of my past criticism," he said this week. "I feel we have to get this right because I'm mayor of the City of New York."
Sanitation Commissioner John Doherty, who has worked for the department for nearly 50 years, said de Blasio is not that different from other mayors when it comes to snow. "He wants the job done, and he wants the streets clear," he said.
De Blasio fielded questions about the storm for nearly an hour Thursday after he officiated at the swearing-in of his new police commissioner. And just a few hours later, he provided another press briefing, this time at the city's state-of-the-art Office of Emergency Management headquarters, flanked by a dozen city commissioners.
Very little had changed from his previous news conference, but it provided the politically precious visual of a leader, surrounded by the latest in technology, in command of a crisis.
"There's always some on-the-job training, but I think so far he's passed the test," Sherrill said. "He may have started to allay any fears that he can't be in charge."