Pennsylvania on Thursday reported its biggest coronavirus-case spike in six weeks; New Jersey officials warned that the virus “is still circulating”; and Philadelphia noted a bump among teenagers, which it said was related to crowds at the Jersey Shore — which likely are about to get bigger over the holiday weekend.

“The virus has not gone away,” said Pennsylvania Health Secretary Rachel Levine, as the commonwealth on on Wednesday added 832 cases, the highest number in its daily reports since May 22.

It was the fifth time in six days the number of new cases has topped 600 in a 24-hour period, an uptick officials have said could be linked to young people drinking and gathering at bars and restaurants that have recently been allowed to reopen.

The state’s total stood at 88,074 cases, with 6,712 virus-related deaths; New Jersey has reported 172,356 cases and 13,251 fatalities.

Philadelphia, where a decline had given way to a plateau, showed another slight uptick with the city reporting 143 new cases on Thursday. Disturbingly, said Health Commissioner Thomas Farley, the data showed that 99 teenagers had tested positive the week of June 14, more than double the numbers for the previous two weeks.

» READ MORE: Despite coronavirus risks, young people are socializing and cases are surging. Psychologists explain why.

He said the Shore was a factor, and given the sultry weekend forecasts, the beaches were likely to be hot destinations this weekend. Temperatures are forecast to crest in the mid-90s Friday and head back to the low 90s Sunday on the mainland.

“We’re seeing cases here in people ... who are going to the beach and staying in a beach house,” Farley said. “They’re going to restaurants and bars when they travel. All this is contributing to the fact that the case count is no longer decreasing.”

The Shore also likely was a factor in new cases in neighboring Bucks County, said its health commissioner, David Damsker. He said that out-of-state travel might account for as many as half the additional cases in the last week. He also mentioned Florida, which on Thursday reported more than 10,000 cases, a new high; Arizona; and South Carolina.

Pennsylvania officials recommended that those who have traveled to those states — and 12 others in the South and West that have reported coronavirus surges — quarantine for 14 days after arriving back in the Keystone State. Similar advisories have been issued in Philadelphia and New Jersey.

» READ MORE: With summer forecasts calling for dangerous heat, pandemic is clouding Philly’s response plans

Meanwhile, with the first heat wave of the season possible early next week, coronavirus concerns were complicating how the city would respond.

Health experts have said that during protracted heat waves, spending even a few hours in a cool environment could save a life endangered by heat symptoms. But nothing is simple in the age of the coronavirus, and sheltering would present social-distancing challenges.

Philadelphia Managing Director Brian Abernathy said the city still hopes to be able to open cooling centers in libraries and senior centers, but the pandemic is a wild card.

”What I don’t want to do is get into a position where I say, ‘These are going to be open,' and then we’re in the middle of virus spike and we’re not able to do that,” Abernathy said. “We have a Plan A, which is to open the centers. Plan B may not be able to open the centers but will provide other resources, and there will be a Plan C and a Plan D.”

Philadelphia on Monday will turn on the water at its 91 spraygrounds. They will be open from 3 to 7 p.m. on weekdays and noon to 5 p.m. on weekends.

And in a move to stimulate some more outdoor life, next weekend the city will close five blocks of East Passyunk Avenue to traffic to create space for outdoor dining and retail businesses. The East Passyunk Avenue Business Improvement District said the stretch from Board to Dickinson Streets will be blocked off from 5 to 10 p.m. Friday, 8 a.m. to 10 p.m. Saturday, and 8 a.m. to 5 p.m. Sunday

» READ MORE: Philadelphia City Council votes to cap third-party delivery fees and expand outdoor dining

This will be the first attempt in the city to close streets to create space for dining since the start of the pandemic. The move comes as the city has pushed back the return of indoor dining to at least Aug. 1.

Efforts to regain some semblance of normality were evident in New Jersey, where Atlantic City casinos reopened, welcoming a relatively small but enthusiastic group of gamblers. This wasn’t your typical casino crowed: No smoking or drinking was permitted, and everyone was wearing face coverings.

While Murphy on Thursday extended the state’s public emergency declaration for another 30 days, he did raise the permitted outdoor gathering size to 500 from 250.

Officials in both New Jersey and Pennsylvania are advising residents and visitors to get used to the mask look. Pennsylvania Gov. Tom Wolf has ordered that masks be worn at all times when social distancing isn’t possible.

» READ MORE: Gov. Tom Wolf mandates wearing masks in public as Pa. and N.J. prepare to reopen attractions

New Jersey Health Commissioner Judith Persichilli advised that the state’s newly reopened amusement parks will be expected to comply with requirements to limit capacity to 50% and require face coverings for staff and visitors.

”COVID-19 is still circulating in our state,” Persichilli said. “It’s up to all of us to stop the spread of this virus.

“Don’t just think about your health, think about the health of your family, your friends, your neighbors.”

Staff writers Bethany Ao, Christian Hetrick, and Marie McCullough contributed to this article.