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

Mississippi is facing "a phenomenal increase in daily reported cases of COVID, and this is entirely attributable to the delta variant, which is sweeping over Mississippi like a tsunami," state health officer Dr. Thomas Dobbs said Thursday.

Dobbs said 97% of new cases are among the unvaccinated, and that 89% of hospitalizations and 85% of deaths are unvaccinated.

Dobbs pleaded with the public to get vaccinated, stressing that the unvaccinated population is driving the current surge, but that vulnerable, vaccinated people are suffering the fallout.

"There is going to be some collateral damage, unfortunately, even folks who've done everything they can to protect themselves," Dobbs said.

"The minority of folks who are vaccinated and hospitalized are overrepresented by the older and those with weaker immune system, so we're seeing a pretty dramatic spillover effect from the transmission in the community to more vulnerable parts of our population," he said.

-ABC News' Soorin Kim