Covid-19 : California’s Governor Warns of ‘Drastic Action’ as Hospitals Near Crisis White House coronavirus adviser Scott Atlas resigns

California’s intensive care units could be overloaded by the middle of December, and its hospitals could be dangerously close to full by Christmas, according to sobering projections that Gov. Gavin Newsom presented on Monday.

And the strain could be even worse in the hardest-hit areas, like the San Joaquin Valley, which was projected to reach 83 percent of its hospital capacity by Dec. 24.

“If these trends continue, California will need to take drastic action,” Mr. Newsom said during a virtual briefing, adding that more severe restrictions, including full stay-at-home orders, could come within the next few days.

California is one of several states that had appeared to have gained control of the virus, only to see it spread rapidly throughout the fall. On Sunday it became the first state to record over 100,000 cases in just a week, according to a New York Times database.

A University of Arizona Covid-19 modeling team recently urged the state of Arizona to take action to stem hospitalizations or else “risk a catastrophe on a scale of the worst natural disaster the state has ever experienced.”

And in New York, Gov. Andrew M. Cuomo said the state will take a series of emergency actions as it faces a new “nightmare of overwhelmed hospitals.”

Already, 99 percent of California’s residents are under a curfew that bans them from leaving their homes to gather or to go to nonessential businesses after 10 p.m. Los Angeles County health leaders have gone even further, announcing a ban on all gatherings in public or at private homes that goes into effect on Monday.

The surge has upended some marquee elements of California’s sports and entertainment scenes. The San Francisco 49ers will play their next two home games in Glendale, Ariz., after health officials in Santa Clara County, Calif., where the team’s stadium is, banned contact sports at all levels through late December in a bid to slow the surge in virus infections there. The U.C.L.A. men’s basketball team announced that its home opener, scheduled for Monday, was being postponed because of its opponent’s virus protocol.

In Los Angeles, residents complained on Monday that a feature film shoot that had been permitted by the city and county’s official film office had shut down a coronavirus testing kiosk at Union Station for a day. City officials said that residents who had testing appointments for Tuesday would be accommodated at any of the city’s other testing locations.

Officials had spent the weekend talking with local leaders and health care providers about their concerns, said Dr. Mark Ghaly, the state’s secretary of health and human services, who also spoke during the Monday briefing.

“Everything is on the table, in terms of how we guide the state through this,” he said. “And we want to make sure what we do is impactful and as time-limited as possible.”

But unlike early in the pandemic, when just a few coastal states bore the brunt, the governor noted that the tidal wave of cases slamming the entire country has limited the likelihood of aid from the federal government or other states.

The total number of coronavirus cases in the United States for November surpassed four million on Saturday, more than double the record set in October of 1.9 million cases. And the sharp escalation is likely to continue after Americans traveled by the millions for the long Thanksgiving weekend. Over 96,000 are hospitalized with Covid-19, a record, according to the Covid Tracking Project.

By contrast, after three weeks of lockdown in England, the number of new cases has fallen 30 percent, according to new data. And after strict measures throughout Europe, a drop in new cases there helped drive down newly reported cases globally for the first time since September, according to Dr. Tedros Adhanom Ghebreyesus, the director general of the World Health Organization.

Mr. Newsom emphasized that California will be able to build on work that the state began earlier this year, including a registry of retired or otherwise nonpracticing health care workers who would be willing to return to work. Eleven surge health care facilities could be prepared quickly to receive patients.

“We don’t anticipate this,” the governor said, referring to the alarming hospitalization figures. “I want folks to know we intend to bend this proverbial curve.”