Tom Bossert, a former White House homeland security adviser and an ABC News contributor, painted a somber picture of the COVID-19 crisis unfolding, saying, "It's too late for any meaningful mitigation" in Gulf states.

Bossert warned that hospital systems in hard-hit states could be overwhelmed within a few days as the delta variant spreads further.

"If this pace continues for the next four or five days, which it seems it will, the hospital systems in Florida and Louisiana will collapse. That's how bad this is. By 'collapse,' I mean they will be full, their ICUs and their hospitals, they will be turning away patients," he said on "Good Morning America" Saturday.

"In some states -- Florida, Louisiana, Texas is looking bad -- all through the Gulf Coast, I believe it's too late for any meaningful mitigation," he continued. "In other words, there is so much disease that what we're seeing is a mathematical certainty."

Bossert urged federal and local governments to focus on providing aid to overburdened hospital systems.

Several San Francisco restaurants have been forced to temporarily close due to a spike in COVID-19 cases.

Aziza, a Moroccan restaurant in the Outer Richmond area, closed after several employees' breakthrough cases.

“We’ve been closed a week, and we’ll be closed probably another week,” co-owner Scott Chilcutt told ABC San Francisco station KGO. He mandated the vaccine for employees in the spring, but three staffers still recently tested positive even after getting shots.

Laurie Thomas, executive director of the Golden Gate Restaurant Association, said there’s only been a handful of recent closures, but each is painful.

"It’s like PTSD again," she said.

The nation’s current seven-day average of 481,000 new COVID-19 vaccinations a day is the highest rate recorded since June 18, White House COVID Data Director Cyrus Shahpar said.

More young Americans are getting shots as well, with the daily average of 12-to-15-year-olds doubling over the last month.

Florida’s COVID-19 cases have continued to soar week after week, with 134,506 new virus cases reported over the past week, according to the state Department of Health.

That beats last week’s weekly record of 110,420 new infections.

Now the weekly case positivity rate in the state stands at 18.9%. There were also 175 virus deaths reported over the past week.

-ABC News’ Joshua Hoyos

The U.S. has seen 864,000 vaccinations in the last 24 hours, the highest daily number since July 3, White House coronavirus response coordinator Jeff Zients said Thursday.

Among those 864,000 vaccinations were 585,000 first shots -- the highest since July 1.

Zients said "Louisiana, Arkansas, Missouri, Alabama, Oklahoma and Mississippi are now vaccinating people at a pace not seen since April."

Tennessee has seen a 90% increase in first shots over the past two weeks and Georgia has recorded a 66% increase in first shots in the last two weeks.

However, seven states -- Florida, Texas, Missouri, Arkansas, Louisiana, Alabama and Mississippi – which have some of the lowest vaccination rates, "account for about half of new cases and hospitalizations in the past week, despite making up less than a quarter of the U.S. population," Zients said.

-ABC News’ Cheyenne Haslett