A tight moratorium on evictions in Massachusetts expired over the weekend, prompting judicial officials and lawyers involved with housing cases to brace for multiple waves of legal actions as court proceedings resume.

Most cases back on track originate from Middlesex, Suffolk and Essex counties — the three counties with the highest numbers of new COVID-19 cases as of Sunday. In the 20 months before the pandemic, the trial court says, landlords across the state submitted an average of about 3,300 eviction requests each month.

Lawyers who represent struggling tenants say they worry that with the lifting of the state ban, renters’ only protection from displacement and increased COVID-19 exposure is a looser federal moratorium that expires at the end of the year.

The state’s six-month moratorium put on hold more than 11,000 pending eviction cases, according to an estimate from the trial court.

The court system did not indicate how many of those cases are immediately enforceable, but Joseph Michalakes, a housing specialist with Greater Boston Legal Services, said those cases threaten to make up the first wave of displacements. The larger picture, he said, will become clearer in several weeks.

"The courts will be busy, and I think they'll be busy signing off on people actually getting evicted, potentially quite soon," Michalakes said.

The federal moratorium, imposed by the Centers for Disease Control and Prevention in September, places a new burden on renters to obtain paperwork and assert their rights. It applies to renters who are being evicted for non-payment of rent and requires them to declare their inability to pay due to substantial income loss, attempts to obtain government assistance and lack of alternative housing options.

Massachusetts court officials have interpreted the CDC order as one that prevents an execution — the final step in removing a tenant — not one that stops all the other stages of the eviction process.

“What I anticipate is that cases, even where the CDC moratorium applies, will continue, but just enforcement will not be permitted,” Michalakes said.

Another wave, he added, will hit the courts next month, at the end of a 14-day waiting period after landlords give tenants legal notice.

Given that mandatory waiting period, Michalakes said, “we really won’t see the scope of how many filings we’re going to get until, more or less, the first couple weeks of November.”

Court officials outlined a similar sequence in eviction cases.

The state’s handling of evictions during the pandemic grew contentious when the legislature first considered a moratorium — with landlords lobbying against it and tenants' rights groups in favor. On April 20, Gov. Charlie Baker signed one of the strongest temporary bans in the country.

Landlords have since advocated for allowing evictions to move forward in order that they might collect money to pay for maintenance and, in some cases, make payments on mortgages.

Meanwhile, housing advocacy groups and progressive elected officials have repeatedly raised alarms about an expected tsunami of evictions, pointing to unemployment rates that reached record levels in the spring. They pushed for a solution that would combine longer-term eviction protection with immediate steps to guarantee counsel for renters and financial assistance to pay rent — money that a diverse committee of housing and health experts would oversee.

Baker, who extended the eviction pause once in July, recently announced an alternative plan to manage the anticipated influx of cases. It includes $171 million for rental assistance, rapid re-housing and mediation efforts, and the temporary rehiring of judges to process the backlog of cases.

Alicia Sasser Modestino, an associate professor of public policy at Northeastern University, said a temporary extension of the eviction moratorium past Oct. 17 would have been beneficial while the Baker administration implements the plan.

“I really think if we could have extended the moratorium for another month or two, it could have made a big difference for several thousand households who are going to be facing eviction,” said Sasser Modestino, a former senior economist at the Federal Reserve Bank of Boston. “And we know that overcrowded housing is one of the ways that COVID spreads. So as people get displaced, they will be doubling and tripling up with friends and relatives, which is just unsafe in terms of a public health policy.”

Sasser Modestino also pointed to national political considerations as a reason she would have recommended an extension. She said the post-election climate in Washington could make a make it easier for Congress to pass another round of cash assistance for people who remain unemployed.

“Right now, there's a lot of political posturing around holding leverage on either side and whose constituents are going to punish them more for not passing a [stimulus] package. But on the other side of that election, no matter who wins, there is no incentive to be delaying anymore,” she said.

Landlords have challenged Baker’s ban in federal court in Boston. U.S. District Court Judge Mark Wolf, who is hearing the case, has signaled he would overturn any attempt to extend the statewide moratorium.

Eloise Lawrence of Harvard Legal Aid Bureau expressed concern on Sunday that the mediation portion of the Baker administration’s plan has not been fully realized and argued the governor’s refusal to extend the moratorium shows he accepts an idea often touted by landlords: that only the threat of eviction can help them negotiate payment plans with their tenants.

“We are in the midst of a complete economic meltdown [through] no fault of the American worker," she said. "They are paying the bills that they can. [Eviction] doesn’t suddenly produce money for rent.”

Lawrence added that the public dollars allotted for rental assistance won’t be enough to satisfy the full amount of unpaid rents throughout the state. More than $40 million has gone unpaid this month alone, according to the Metropolitan Area Planning Council.

“Landlords who went into the business of making their money through residential real estate have to understand that when the economy goes down, they too are going to make less money,” she said.

Landlords, meanwhile, point to the federal moratorium as still providing some protection to renters through the end of the year.

The CDC said the temporary halt was a public health measure to prevent the spread of COVID-19.

GBH News' Mark Herz contributed to this report.