D.C. Mayor Muriel E. Bowser (D) said Friday that people planning to attend an August rally for racial justice should follow the District’s guidance for travelers, including a self-quarantine order for visitors from coronavirus hot spots.

The mayor’s order, which went into effect Monday, requires a 14-day self-quarantine for anyone coming into Washington after “nonessential activities” in one of 27 states considered high risk. The order is in effect through the fall, but Bowser has signaled she could relax it.

“If we have a quarantine order still in effect, I have to emphasize that no one should look at the quarantine order as a punishment, okay?” Bowser said. “People who are making personal decisions to travel, or other activity for that matter, have to consider how it impacts other people.”

City officials have acknowledged that authorities would not be able to widely enforce the order, although anyone who “willfully violates” it can be charged with a misdemeanor and fined up to $1,000.

The Aug. 28 rally, organized by the Rev. Al Sharpton, aims to bring 100,000 people to the nation’s capital on the anniversary of the March on Washington. It would be the largest mass gathering in the city while coronavirus cases have been on the rise.

Asked whether she would discourage people from gathering for the rally as she did with Fourth of July festivities, Bowser said she would “consider what the health metrics suggest closer to that time.”

Prince George’s County Executive Angela D. Alsobrooks said late Friday that the county’s rising caseload prompted her to limit crowd sizes in most instances — including social, religious and recreational events — from 100 to 50 people. The new executive order takes effect at 5 p.m. Saturday.

“We are not afraid to take decisive action to protect the health and well-being of our residents, and at this point, the data tells us that this new restriction is unfortunately necessary,” Alsobrooks said in a statement.

In neighboring Montgomery County, health officer Travis Gayles announced late Friday that the county is requiring all nonpublic schools to stay closed to in-person instruction through Oct. 1, although Gayles said he would reexamine the requirement as that date approached.

“At this point the data does not suggest that in-person instruction is safe for students or teachers,” Gayles said in a statement. The county’s public schools plan to have virtual instruction only.

In Ocean City, a new mask mandate was issued Friday to require beachgoers to wear face coverings on the boardwalk, Mayor Rick Meehan announced.

The requirement is stricter than the new masking order that Maryland Gov. Larry Hogan (R) issued earlier this week, and it applies to all outdoor areas on the boardwalk, even if social distancing is possible. It will be enforced daily from 8 a.m. to 2 a.m.

Worcester County, which includes Ocean City, recorded 32 new coronavirus cases Friday — its highest daily total since the start of the pandemic. The region has seen an increase in caseloads during the past three weeks.

Hogan’s statewide order, which also went into effect at 5 p.m. Friday, requires residents older than 5 to wear face coverings while indoors in public spaces and outdoors when social distancing is not possible. Masks are required at all businesses, commercial office buildings and locations that have public areas, including houses of worship, casinos, gyms and personal-service establishments.

After saying this week that house parties are a large source of coronavirus spread, Hogan on Friday asked Maryland residents to use caution during weekend activities.

“As we head into the weekend, Marylanders should keep in mind that the top activities reported in contact tracing investigations were family gatherings, house parties, and outdoor events,” he said in a tweet. “It’s easy to become complacent, but we can’t afford to let our guard down.”

Hogan on Friday issued the fourth extension of a moratorium on phone, cable, water, gas and electricity shut-offs for residents who cannot pay their bills. Late fees are also prohibited. The moratorium now remains in place until Sept. 1.

Meanwhile, the Arlington County Board on Friday passed an emergency ordinance that bans groups of more than three people from congregating on sidewalks and streets that are posted with the restrictions and requires those who are walking to stay at least six feet away from others in those areas. Violations could include a traffic fine of up to $100, the county said in a news release.

In a statement, Board Chair Libby Garvey said the move came after it became clear some residents were not wearing masks or social distancing.

“The Board hopes that this step will make it clear to our entire community that this pandemic is far from under control and that we are serious about maintaining social distance to slow its spread and save lives,” Garvey said.

Maryland, Virginia and the District added 2,222 infections Friday, bringing the region’s total to 190,360 since the start of the pandemic. The three jurisdictions reported 39 new fatalities, lifting the death toll to 6,252.

D.C. added 69 new cases and one death, Maryland had 1,169 new cases and five deaths, and Virginia reported 984 new cases and 33 deaths. That’s the highest number of coronavirus-related fatalities in a single day in Virginia since May 28.

The seven-day average of daily caseloads in D.C., Maryland and Virginia stood at 2,083 on Friday, just below the roughly 2,200 daily average recorded at the height of the pandemic.

Much of the recent increase is a result of spikes in the Hampton Roads area of Virginia and in the Baltimore metro area, although two Washington suburbs Friday recorded their highest daily totals in weeks. Prince George’s County saw its largest number of infections since May 30, while Montgomery County’s was the highest since June 13.

The District’s caseload has generally held steady in the last half of July, while Northern Virginia’s daily cases are little changed since mid-June.

Erin Cox, Ovetta Wiggins and Julie Zauzmer contributed to this report.