It was so hot this week that even the waves at Joseph Sylvia State Beach looked limp. A heavy haze rested on the horizon, matched only by the wall of heat and humidity that hit anyone who ventured outdoors, leaving some short of breath. The heat put a strain on the power supply, and on Monday and Tuesday there were widepsread brownouts and blackouts.

But even though the heat wave that struck the Vineyard along with most of the East Coast early this week left 4,800 Island residents without electricity one evening and caused one or two sleepless nights that even a fan couldn’t help, Islanders and visitors fared well considering the circumstances.

After a 91-degree day on Monday, a transformer failed on Eastville avenue in Oak Bluffs, causing parts of Edgartown, Oak Bluffs and Vineyard Haven to lose power on Monday evening around 5 p.m. Fans stopped blowing, ice cubes became water again and air conditioning units went quiet.

“We’re expecting to hit levels [of electricity use] that have not been seen since 2006,” Mike Durand at NSTAR said on Tuesday, when the thermometer climbed to a high of 94 degrees. “You’re bound to have an outage somewhere on any electricity system, but our system has held up really well over the past few years,” he said.

Mr. Durand said NSTAR was not anticipating any more problems this week due to a $1 billion investment in improvements to their system in preparation for summer months. He said most customers had electricity restored within 45 to 50 minutes of the outage. “Last year was much colder than normal,” Mr. Durand said. “We can be in this range and not hit peak usage.”

boogie boards
Boogie boards are useful aid when temperatures climb into the 90s. — Ray Ewing

With temperatures in the uppers 80s and 90s, the Massachusetts Department of Public Health issued a statewide heat advisory for the week and the Environmental Protection Agency issued a poor air quality alert. A heat wave is caused by a system of high atmospheric pressure, when air from upper levels of the atmosphere condenses and descends, increasing temperatures.

The Martha’s Vineyard Hospital saw no cases of heat exhaustion, but did urge caution, especially to people who spend large amounts of time outdoors. “Our advice is to regularly hydrate yourself,” Rachel Vanderhoop, director of development, said. “If you’re working or playing in the sun, take regular breaks in a cool spot and be aware,” she added.

Meanwhile, hardware stores saw a run on fans and air conditioners. “I just can’t believe it, everything’s gone,” said John Montes at Edgartown Hardware. “I had a lot of fans and they’re all gone. It’s just unbelievable.” Mr. Montes said he had a few fans left, and had put in a special order expected to arrive today.

A spokesman at Shirley’s Hardware in Vineyard Haven said they saw sales spike too in fans and air conditioners, but had not sold out.

At Scoops in Edgartown the story was drinks, drinks and more drinks all week long, with workers reporting an increase in sales of smoothies, iced coffee and iced drinks all around. The after-beach rush brought in crowds seeking bowls of ice cream.

Children and seniors are most challenged during heat waves. Ann Wallace at Island Elderly Housing said all the residents either had air conditioning or fans in their rooms. “Anyone can go to a cool place,” Ms. Wallace said of the residents, emphasizing their access to the cool community rooms in the facility. Her advice to the elderly this week was to limit their activity and “drink lots and lots of water.”

Linda Cook
Linda Cook lines up to buy two air conditioners. — Ray Ewing

And people aren’t the only ones at risk during extreme heat. Dr. Bridget Dunnigan at the Vineyard Veterinary Clinic in Edgartown said the clinicians had seen a handful of heat-related issues this week, and she encouraged pet owners to walk their dogs in the early morning or late in the day. She also reminded owners that with the summer crowds come more cars, and it is important to keep dogs leashed or fenced in when they are outside.

Seen in Edgartown this week: a fan on the handlebar of a stroller, kids riding bikes in bathing suits. “Come On In — AC is On!” declared a sign on the door of Edgartown Books.

Felicia Cheney at the Edgartown Public Library confirmed the indoor trend. “They come in and probably stay longer,” Ms. Cheney said. “And drink a lot of our water,” she added.

Sid and Suzy Halpern of Glen Cove, N.Y., stood in the shade of a tree on North Water street. Mrs. Halpern was resting a cup of iced coffee on her husband’s head, while their daughter Amanda was at Mad Martha’s getting an ice cream. She brought her dad an extra spoon. “We’re doing pretty well, we’re so happy to be here,” Mrs. Halpern said.

“We’ve never seen heat like this,” she added, referring to previous summer visits to the Vineyard. Mr. Halpern said they decided to rent a car instead of scooters because of the heat.

A few blocks away, Theresa Bassett and her two small children sat on a bench in the shade of Nevin Square, waiting for Toy Story 3 to start. “We’re doing fine,” she said, “a little grumpy between the kids but otherwise okay.” She turned to her son to ask how he was feeling in the heat; he said he’d like to go to the beach and stay in the water the whole time.

And that’s exactly what Camp Jabberwocky did on a late afternoon this week at State Beach. Splashing around, campers enjoyed the relief of the water as counselors brought out floats, boats and kayaks for all to enjoy.

The beach was crowded for late afternoon. “It feels especially good after feeling so awful all day,” one swimmer said. “It almost makes it worth the suffering,” her friend added.

Lily Walters, field manager at Morning Glory Farm, said the entire field crew piled into a truck and headed to South Beach on Tuesday after a long day in the heat. “We’re plugging through it, kind of melting,” Ms. Walters said. “We were watering the plants with our sweat yesterday.”

Ms. Walters made sure her entire crew was drinking loads of water throughout the day, adding that everyone kept an eye on each other.

“Luckily straw hats are really in this year,” Ms. Walters said, smiling over the phone. “So everyone’s sporting those.”