COVID-19 updates: More than 10,000 new deaths reported in US in 1 week

The superintendent of schools in Lee County, Florida, informed parents and staff Monday night that he is reversing the mask mandate he imposed for students and will now let parents opt their children out of wearing face coverings.

In a letter, the superintendent, Ken Savage, said that last week's ruling by an appeals court allowing the state to continue sanctioning mask-requiring districts, led him to reverse course.

"Last Friday, the 1st District Court of Appeal instituted a stay, which means the Florida Department of Education can continue to enforce its interpretation of the parental opt out until this matter is ultimately resolved. Therefore, starting on Tuesday, September 14, the School District of Lee County will require face coverings, while allowing parents to opt-out without a medical exemption," Savage said in statement.

Lee County was one of at least 13 districts in Florida defying Gov. Ron DeSantis and requiring masks for students unless they provided a doctor's note exempting them from wearing one.

Savage implemented a mandate on Sept. 1, effective for 30 days, while the district tracked coronavirus-related numbers.

-ABC News' Will McDuffie

Florida Gov. Ron DeSantis is threatening to sue cities in the state that have issued vaccine mandates, for up to $5,000 per infraction.

The governor, who early Monday repeated falsehoods about the COVID-19 vaccines, said hours later, at a press conference, that he's willing to sue the cities because he does not want vaccine mandates to threaten Floridians' jobs.

"We are not gonna let people be fired because of a vaccine mandate," he said.

Meanwhile, over 11,215 patients remain hospitalized in Florida with COVID-19, according to the Florida Hospital Association.

As of Monday, 75% of the state's eligible population has had one vaccine dose, according to the U.S. Centers for Disease Control and Prevention.

-ABC News' Matthew Vann

A federal judge issued a temporary restraining order that ordered Iowa officials to stop enforcing a law passed in May that prevents school boards from enforcing mask mandates.

Judge Robert Pratt said the parents who are suing Gov. Kim Reynolds and state and local education offices, have demonstrated that an "irreparable harm exists" if masks aren't used and required.

The judge said he looked at data on the effectiveness of masks to reduce the spread of the coronavirus and agrees with recommendations from the Centers for Disease Control and Prevention and the American Academy of Pediatrics on mask wearing in schools.

The order will stay in effect until the court issues an order for a preliminary injunction.

Thomas Ahart, the superintendent of Des Moines Public Schools, called the judge's decision "welcome news."

"I will reinstate a mask mandate – as we had in place for most of last school year – for all students, staff and visitors to Des Moines Public Schools," he said in a statement.

-ABC News' Matt Foster

The U.S. daily death average has now surged to nearly 1,200 -- six times the death average of 191 from two months ago, according to federal data.

On Friday alone, the U.S. reported approximately 1,860 COVID-19 deaths -- the highest single-day figure in nearly seven months, though that figure may partially be the result of data backlogs from the holiday weekend.

Even with current data still skewed from last week's holiday, this summer's surge has far surpassed the figures from last summer, and national case metrics are about four times higher than one year ago, according to federal data.

Kentucky and West Virginia are seeing more new cases and hospitalizations than at any point in the pandemic. Other states like Georgia and Oklahoma also showing signs of exponential growth in cases and hospitalizations.

-ABC News' Arielle Mitropoulos