Jennifer Fitzpatrick, 32, of the District, and her 11-month-old daughter Lily spent Thursday afternoon at Upshur Pool to cool off. (Sarah L. Voisin/The Washington Post)

As the Great Washington Heat Wave headed toward its crescendo, Tony Hurst’s adventure camp offered water two ways: spray-bottle misting and squeeze-bottle “bird drinks.”

“We drip a little drink into their mouths, so we don’t have lips all over the bottles,” Hurst, a librarian at the private Beauvoir School in Northwest Washington who has been running the camp for 13 years, said Thursday. “Water is our air-conditioner. We have to make sure everybody’s a little bit wet.”

It was the eighth consecutive day with temperatures over 90 degrees in the Washington region, with a high of 93 degrees and a heat index of 103 at Reagan National Airport, according to the National Weather Service. The next four days are expected to be even hotter.

The Washington Post’s Capital Weather Gang said temperatures in coming days could reach 100 degrees, for the first time since 2016, with heat index values up to 115. An “excessive heat warning” was issued through Sunday.

Hurst made sure that his 225 campers were at places with air-conditioning or water, such as the Kennedy Recreation Center in Northwest or Yards Park, in Southeast Washington, by Nationals Park. On Wednesday, they visited the Naval History Museum. Friday, they will be at Miracle Theater.

Local governments have activated heat emergency plans and are spreading the word about places that are open to the public where people can cool off.

In the District, Mayor Muriel E. Bowser (D) extended hours at some pools and splash parks until 9 p.m. through Sunday night and announced that low-barrier shelters for people who are homeless will be open 24 hours. Cooling centers are open in publicly accessible government facilities, homeless shelters and senior citizen wellness centers until 6 p.m. or until it has been deemed safe to be outdoors.

At Upshur Pool in Northwest Washington, one of the facilities with extended hours, Nicole Jackson, 24, cradled 3-year-old Laila in the water.

“I can’t keep my daughter trapped inside or go to a playground,” said Jackson, who is five months pregnant. “The pool, in my opinion, should stay open all summer, all the time.”

The D.C. Fire and Emergency Medical Service logged 10 calls for heat exhaustion and heatstroke on Wednesday, the most of any day this month except the Fourth of July.

District Heights resident Anastasia May, 88, escaped her un-
air-conditioned home by heading to the icy cool casino at the MGM National Harbor. She has rules: No more than two hours a day, and quit when her losses reach $50.

On Monday, the retired car dealership clerk won $400 and celebrated at a nearby IHOP with her son Thomas, 52, who lives with her. On Thursday, they were working a jigsaw puzzle of Notre Dame at home when they decided it was too hot to stay there. The casino is a 20-minute drive away.

Her son sits upstairs at the casino and reads puzzle books while she plays the odds.

Those who had to be outside coped as best they could.

Dressed in thick, fire-resistant uniforms, a PowerComm Construction crew installed water and power pipes at the intersection of Harvard and 13th Street NW at midday. They took turns going down into the cooler, makeshift tunnels for 30 minutes at a time.

Foreman Albert Tapia, 29, said Thursday’s temperatures were bearable but he knew the heat would be spiking on Friday and beyond. Earlier this week, he was told that he would be getting Saturday off because of the heat.

“Every year, it’s just been getting hotter and hotter,” said Tapia, who has worked in construction for 13 years. “It’s not easy, but you do what you’ve got to do to feed your family.”

Arlington County reminded cool-seeking residents that MedStar Iceplex, where the Washington Capitals practice, was open, along with the county’s libraries, community centers, parks and pools. Fairfax County warned residents not to leave children, pets or the elderly alone in parked vehicles, where temperatures spike even more quickly than outdoors. Montgomery County urged the public to avoid strenuous activities and overexposure to the sun.

The Maryland Jockey Club has canceled its live horse races at Laurel Park this weekend because of the heat. Simulcasting of races elsewhere and betting will go on as normal, the club said.

The 14 Freshfarm farmers markets in the District, Maryland and Virginia plan to operatethrough the weekend despite the heat, said Molly Scalise, the organization’s communications director.

“We always encourage our shoppers and vendors to take precautions because of the weather, whether it’s rain or high heat,” she said.

The high temperatures have not affected supply or demand, but she noted that it’s peak season.

“On the really brutal days, it does slow down a bit,” she said. But she noted that most of the markets open at 9 a.m., so devoted fruit and vegetable lovers can arrive before the sun gets too scorching.

The heat wave might have troubled Mike Eggleston decades ago, at the start of his 40-plus year career in construction — but not any more. Eggleston, 60, has worked in subzero frigidity and in blistering sunshine. He has confronted digging sites frozen solid and he has seen workers carted away to the hospital after suffering heat strokes.

Determined to keep his team of about 30 workers healthy as they build a new Hyatt Hotel in National Harbor, he implemented his recipe for surviving the sauna, honed through years of experience.

Number one, educate the workers at 20-minute briefings every morning about 6:30 a.m. Eggleston and the others talked about how it’s necessary to drink “a little water, a lot of the time”: about six to eight ounces, twice an hour.

Two, switch up the dress code. Counterintuitively, it is actually better to don light, long-sleeved shirts when temperatures spike, Eggleston said. Not only does it protect workers from sunburn, but when they sweat the moisture lingers, cooling the whole arm.

Increase the supply of water bottles and water coolers. And shorten the workday — 10 hours maximum instead of 12. Allow breaks whenever workers need it.

“We knew it was coming,” Eggleston said Thursday. “We actually plan on it all year. You have little spikes like this every summer.”

Asked to choose between extreme cold and extreme heat, Eggleston said he will always pick the latter.

“It’s tough when you can’t even pour concrete,” he said. “You can do a lot more construction activities when it’s hot than when it’s cold.”

Ovetta Wiggins, Fenit Nirappil and Erin Cox contributed to this report.

Excessive heat watch Friday through Sunday as DC faces 100-degree temperatures

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