One-third of deaths from Hurricane Beryl in Texas were caused by heat. The victims’ families say they should still be alive.

Two days later Hurricane Beryl hit Texas, Janet and Pamela Jarrett still didn’t have power in the Houston home the sisters shared. A heat advisory was in effect.

They spent the evening playing Pamela’s favorite game, Connect 4. Everything seemed fine.

But the next morning, Janet found Pamela, 64, who was disabled and used a wheelchair, having trouble breathing.

“I heard her breathing heavily, gasping for air,” Janet said. “This is something that never leaves your head. This won’t go away. Even when I go to sleep and I’m lying there, I hear it. It’s like I’m living it all over again.”

Pamela died on the way to the hospital on July 11. Official cause of death: hyperthermia due to exposure to environmental heat.

The same cause of death is listed for a third of the 21 confirmed Texas deaths caused by Hurricane Beryl, meaning they happened not because of the typical threats a storm brings — flooding or falling trees — but rather as a result of the strong heat in the middle of widespread power outages during and after the storm. Heat indexes, or “sensitive” temperatures, soared into triple digits in the days after the storm.

The tragedies highlight how ill-equipped Texas (along with many other parts of the country) is for extreme weather events that are becoming more frequent and intense due to climate change — especially when multiple disasters collide. The deaths also show how the line between one type of fatal environmental disaster and another can easily become blurred.

The death toll from Beryl, Texas, will likely continue to rise, and heat-related fatalities are intensifying scrutiny of local utility CenterPoint Energy and state leaders.

“She didn’t have to die like that,” Janet said of her sister. “I’m angry because I didn’t get an answer. I couldn’t call anyone. I’m angry at CenterPoint for not doing a better job. I’m just angry about everything.”

More than 2 million homes and businesses were affected by outages caused by Hurricane Beryl, which made landfall as a Category 1 storm. In a statement to NBC News, CenterPoint said it intends to do a “thorough review” of its response to the storm .

“We want to express our condolences to the families and friends of those whose lives were lost as a result of Hurricane Beryl,” the dealership said.

CenterPoint officials said the company mobilized teams as soon as it could and worked hard to resolve the outages.

Janet Jarrett endured nine days without power in total, during which she said indoor temperatures were nearly 100 degrees Fahrenheit, even at night. She spent a week in that heat after her sister left.

Janet said she did her best to keep Pamela cool, using cool cloths and taking her outside when there was a breeze. But, as with most victims of heat-related illnessesthe symptoms were not obvious until it was too late.

“I didn’t even know there was anything really wrong with her,” Jarrett said. “It wasn’t something I could detect because she was talking and responding to everything and being normal.”

Jesus Rodriguez, a 52-year-old Houston resident, also had no idea anything was wrong with his 78-year-old father, Oscar. On July 10, the third day without power, Jesus said he checked on Oscar in the morning, bringing him water and an ice-cold Diet Coke from a cooler.

When Jesus returned in the afternoon, his father “was lying down, as if he were sleeping, but breathing with difficulty,” Jesus said. “I hardly thought anything about it, but when I tried to wake him up, he didn’t wake up. That’s when I called 9-1-1.”

Oscar died that day at Memorial Hermann Greater Heights Hospital in Houston. Jesus described his father as a devoted family man who was healthy for his age.

Its power has been interrupted during previous storms, but never for more than a few days.

“This was definitely the worst,” Jesus said. “It was almost a week and a half before I got my energy back.”

He blamed CenterPoint for being slow to respond and not communicating sufficiently.

“If they had said, ‘We won’t get to your house for a week and a half,’ maybe I could have convinced my father to go somewhere else,” Jesus said.

Three Houston-area hospitals said they saw a significant increase in emergency room visits because of the heat after the storm.

Ben Saldana, associate medical director at Houston Methodist Hospital, said the facility had the highest number of emergency room visits since the Texas big freeze of 2021.

“All of our emergency rooms pretty much doubled their normal arrivals on the day of the storm,” Saldana said, adding, “We’re not back to normal yet.”

Doctors at the hospital have linked the health problems of 525 patients to the effects of heat since July 4, he said.

Even people who did not suffer fatal consequences from the heat described punishing conditions due to power cuts.

Deja McClendon, who lives in Humble, Texas, was without power for six days and split her time between her apartment, her boyfriend’s mother’s apartment and a hotel to beat the heat. The chaos forced her to take time off work, she said.

“Texas is a different kind of animal when it comes to heat,” McClendon said, adding, “It was very, very stressful having to move around a lot.”

Talrah Christie, who is five months pregnant, lost power for five days in Conroe, Texas, which is served by the energy company Entergy Texas. She said the post-Beryl disruption was the worst she could remember.

“I tried to endure [the heat] the first two days, and after the second night, I thought, this is almost becoming a medical problem. I can’t stay here,” she said. But Christie and her husband couldn’t find any available and affordable hotel rooms nearby, so they resisted.

Texas Governor Greg Abbott demanded an investigation into CenterPoint’s response following the storm, although Abbott himself also faced criticism for being on an economic development trip to Asia when the hurricane made landfall.

Rep. Sylvia Garcia, D-Texas, also took aim at the dealership. Several of heat-related deaths after Hurricane Beryl occurred in his district.

“CenterPoint’s inability to restore power quickly created a public health crisis worsened by extreme heat,” she said in a statement to NBC News.

Janet Jarrett said she hopes preventive measures are taken so others don’t suffer losses that could have been avoided.

“This shouldn’t have happened. We had a lot of plans. They took all of that away from her,” Jarrett said. “And now I’m here trying to bury her.”

This article was originally published in NBCNews. with