Progress: Even as ICU availability jumps, Bay Area remains on lockdown.

Intensive care unit availability in the Bay Area jumped to 23.4% on Saturday after weeks of singledigit availability, a strong signal that the worst of the surge is in the past.

Nonetheless, it was not immediately clear when the region could emerge from the state’s stayhome order. The order is supposed to be lifted when ICU availability is projected to exceed 15% looking four weeks ahead.

The Bay Area is well beyond that threshold.

The 13county Sacramento region saw its stateimposed lockdown lifted more than a week ago. But the ICU availability there remains at 11.9% — a little more than half the Bay Area’s current figure.

State health officials could not immediately be reached Saturday to discuss when the shutdown might be lifted for the Bay Area, and why the Bay Area remained locked down while Sacramento was not.

The numbers are looking good, Matt Willis, Marin County’s public health officer, told The Chronicle.

Lifting the Bay Area lockdown is “the state’s call,” he said. “But we’re all looking at the same numbers, and we’re all feeling hopeful.”

San Francisco Mayor London Breed said Friday that the city may “soon start reopening under California’s guidelines.”

Lifting the lockdown would allow the resumption of activities permitted under the state’s purple tier, including outdoor dining and indoor service at hair salons. But counties sometimes also bar activities, separate from the state’s order.

California health officials use a complex formula to anticipate future ICU availability. “At the moment the projections are not being shared publicly,” Department of Public Health spokeswoman Ali Bay told the Associated Press. When the Sacramento region’s order was lifted, ICU availability was about 9%.

The lack of a state explanation has created confusion, and that’s the opposite of what the state should be doing, said David Canepa, president of the San Mateo County Board of Supervisors. But the numbers look encouraging, he said.

“My concern is that the public will hear this and think it’s safe to go out with a business as usual attitude,” he said. “I too would like to dine in at my favorite restaurants, but for now I will stay at home and order takeout.”

For now, he said, “stay home if you can, avoid gatherings and wear your damn masks.”