The U.S. Centers for Disease Control and Prevention revealed new COVID-19 forecast models Tuesday that showed daily hospitalizations could more than double by mid-September.

By Sept. 20 the U.S. could see hospitalizations as high as 27,000 a day, according to the agency's models. Currently the seven-day average of COVID-19 related hospitalizations is 12,190, according to the CDC.

The peak seven-day average was 16,492 in January, according to health data.

The low-end of the CDC's forecast's models is 7,800 hospitalizations a day.

Health officials stress that a change in behavior, including masking, vaccination and social distancing, will reduce severe illness and hospitalization.

-ABC News' Brian Hartman

There are currently no COVID-19 intensive care unit beds available in the state of Arkansas, a situation Republican Gov. Asa Hutchinson referred to as a "cautionary note for everyone" Tuesday.

"It fluctuates day by day. But right now, because of the increased number of COVID patients that need that type of ICU care, those beds are full," Hutchinson told reporters.

There are still ICU beds available for non-COVID patients, Hutchinson noted.

Arkansas lags behind the national average in vaccinations. As of Monday, 52% of residents had received at least one dose, and 40% were fully vaccinated, according to the Centers for Disease Control and Prevention. By comparison, 61% of Americans have gotten at least one shot and 52% are fully vaccinated.

-ABC News' Libby Cathey

Dr. Francis Collins, director of the National Institutes of Health, said he expects children ages 5 to 11 in the United States to become eligible for COVID-19 vaccination toward the end of the year.

"Keep in mind, kids are not just scaled down adults -- they have different immune systems and metabolisms. You really have to do the careful trials to make sure you got the dose right and there aren't any surprises," Collins told ABC News' George Stephanopoulos in an interview Tuesday on "Good Morning America."

"Realistically," he added, "I don't think we're going to see approval for kids under 12 until late in 2021."

4:02

NIH director talks about full FDA approval for Pfizer vaccine

Dr. Francis Collins discusses how news of the Pfizer COVID-19 vaccine receiving full approval from the U.S. Food and Drug Administration might affect vaccination rates across the country.

Collins also said there is “no reason to be too confident” that the country has hit its peak and that case numbers will start to come down.

"When I look at the data, it's still going up awfully steeply. More than 150,000 cases a day and that number keeps growing; hospitalizations [at] 95,000; deaths now averaging a 1,000 a day," he noted. "Florida, Louisiana, Mississippi, Alabama -- there's just a world of hurt going on there with so many unvaccinated people and hospitals really struggling to try to manage all the really sick people who are coming to their emergency rooms."

The delayed 2020 Summer Paralympics kicked off in Tokyo on Tuesday as Japan grapples with a growing COVID-19 crisis that has showed no signs of slowing down.

Protesters calling for the Games to be canceled gathered outside the Olympic Stadium in Japan's capital ahead of Tuesday's opening ceremony. Like the 2020 Olympics, which ended on Aug. 8, this year's Paralympics is taking place amid a state of emergency. More than a dozen Japanese prefectures, including Tokyo, are currently under emergency measures related to COVID-19. The Tokyo Olympics and Paralympics were both postponed a year due to the pandemic.

Japan's daily number of newly confirmed COVID-19 cases has been breaking records in recent days and weeks, while the daily death toll has stayed below the record 216 fatalities reported on May 18. The Japanese government and the Tokyo metropolitan government issued a joint appeal on Monday to hospitals in the capital to admit more COVID-19 patients as cases rise.

"The delta variant's strong infectiousness just isn't comparable to previous ones," Japanese Health Minister Norihisa Tamura said as he stood alongside Tokyo Gov. Yuriko Koike. "We would like to have further support from the medical community to secure hospital beds for coronavirus patients."