The storm clouds over Mayor Eric Adams’ young administration — a tsunami of migrant arrivals, yawning deficits, an ever-worsening housing crisis — grew darker this week following the stunning resignation of his history-making police commissioner, Keechant Sewell, sources and experts say.

Sewell’s departure comes as City Hall is in the midst of two showdowns with the City Council — talks over the Big Apple’s $106 billion spending plan for 2024 are grinding onward while Adams is pushing back against an expansion of the city’s housing voucher program that he bitterly opposes but may not have votes to sustain a veto.

“It looks like a process of repetitive flailing because there isn’t a larger vision,” said David Birdsell, the former longtime dean of Marxe School of Public and International Affairs at CUNY-Baruch, who is the provost at Kean University in New Jersey. “There is no center that holds.”

“What Bloomberg did was to sketch a vision of the city where crime was low, business was robust, the city had more parks,” he continued. “Whether you liked it or not, there was a vision.”

“Mayor Adams promises successful responses to problems, starting with reaction not vision, so he’s always on his back foot,” he said. “And then he’s always putting himself at the center of the solution and not his team.”

Adams’ City Hall has initiatives — for example, on crime and housing — but they seem scattershot, Birdsell said.

Compounding that, he added, Adams and his inner circle operate as if they are trying to run the entire city themselves, an approach that becomes impractical when handling dozens of agencies. By contrast, Bloomberg empowered his commissioners and largely stayed out of their way.

Adams defended his management style and batted back questions about the extraordinarily high level of turnover during the first 18 months of his administration at his first press conference since Sewell quit.

“I have 320,000 employees,” a combative mayor told reporters, describing his management style as “very unique.”

“People come and go. You don’t sign up and say “I’m a lifer, you come, you provide your expertise,” he added. “I do not stand in the way of a person’s desire to pursue their careers.”

Allies and longtime hands in politics were blunt in private, directly linking City Hall’s struggles to hire and retain talent to Adams’ failure to establish a larger vision for his administration and preference for stocking his inner-most circle with longtime friends and allies.

“It’s about putting the right people in the right place,” said one. “Some of the individuals he puts in place, they’re friends, it’s patronage; that never works out,” the person said.

“They hire a pro and then they cut her legs out,” the person added. “They didn’t allow her to hire, they didn’t allow her to bring in a team, they didn’t allow her to operate.”

The result, the person said: “It’s chaos.”

Adams’ City Hall has confronted an extraordinary level of turnover in key posts during its first 18 months running the Big Apple: Hizzoner’s first chief-of-staff, Frank Carone has left; ditto First Deputy Mayor Lorraine Grillo; and his head of intergovernmental affairs, Roberto Perez.

Housing czar Jessica Katz, top legal adviser, Brendan McGuire and communications director Maxwell Young, who coordinates the administration’s media strategies, have all announced plans to depart before the end of summer.

That wave of voluntary departures comes on top of City Hall seeing both Buildings Commissioner Eric Ulrich and Social Services Commissioner Gary Jenkins resign amid scandal.

“You can’t be appointing your friends every other day,” said another. “There are a lot of people looking and waiting for his vision of New York City.”

“Every day there’s a flag raising, every day there’s a gala,” the second person added. “He really is getting around the city. But is getting around the city running the city?”

Opponents of City Hall have leapt on the perception that Adams didn’t have Sewell’s back.

Sewell quit just hours after The Post revealed that Adams had taken an even heavier hand running the department after she approved disciplinary action against a longtime friend of the mayor who was caught on tape canceling out an arrest.

“I empathize with the unique challenges she faced that are so familiar to many of us in positions that have not traditionally been held by those who look like us,” said Council Speaker Adrienne Adams (D-Queens), who sits across the table from Hizzonner in the contentious budget talks.

But Adams is hardly the first mayor to lose a high-profile commissioner or be dealt a string of non-stop crises — including when former Mayor Rudy Giuliani fired his high-profile Police Commissioner Bill Bratton after he appeared on the cover of TIME Magazine.

Giuliani, a Republican went on to win his second term in a landslide in a heavily Democratic city.

“People didn’t care, despite Bill Bratton, despite all those things,” said veteran political strategist Chris Coffey, a veteran of the Bloomberg administration who was the chief strategist to Andrew Yang’s mayoral campaign in 2021. “He crushed the Democrats in a Democratic town because he drove down crime.”

He added: “This mayor was elected on public safety.”

Another longtime strategist, Hank Sheinkopf, offered similar advice.

“He’s got 3 big problems: migrants, crime as there’s still a sense to the citizens that crime is up and it’s the budget,” said Sheinkopf. “You always get departures after the first year and a half. He has to get this house in order quickly.”

List of departures:

*Departing later this summer