Deadliest weather? You’re in it. How to stay safe in a blazing North Texas summer

Karl Simmons was mixing glue to lay down the turf in Gateway Park on a July afternoon in 2018. It was 95 degrees outside, and the sun was beating down.

Simmons was new to the job. After just three days on the work site, his body hadn’t yet adjusted to the stress of the heat and the exertion of physical labor in the summer sun.

Simmons, 30, called his wife and complained about the heat. He told his supervisor he wasn’t feeling well. He went back to work to bring $2 million in upgrades to the Fort Worth park.

At about 4 p.m. a coworker realized Simmons was lying on the ground. He was “vomiting, having difficulty breathing, non-responsive, and bleeding from his mouth and nose,” according to a lawsuit filed by Simmons’ family against his employer. His body temperature was recorded at 107.1 by emergency responders at the park.

Simmons was pronounced dead within two hours, and his cause of death was determined to be heat stroke, according to his autopsy.

Simmons was one of hundreds of Texans who die from heat stroke every year. Heat is the deadliest weather event in the U.S. It kills more people each year than hurricanes, flooding, wildfires, freezes, or any other type of extreme weather, experts said.

“It’s ironic that out of all of the parts of climate change, that’s the most obvious one that we should have been thinking of,” said Ladd Keith, an urban planner and professor at the University of Arizona. “But it’s the last one that we’re addressing.”

Three stages of heat illness

Generally, heat-related illness progresses through three stages.

First, are heat cramps. Your muscles may spasm or seize when you’re exerting yourself in a hot environment. Those can usually be relieved on their own, without medical attention.

Next is heat exhaustion, where if you’re spending time outside or in hot weather, you might feel a little nauseous or dizzy, but usually if you go inside or drink some water, you should be able to cool down on your own, said Dr. Stefan Meyering, an emergency medicine physician at JPS Health Network.

The most serious is heat stroke, which is generally considered to occur when the body’s core temperature has risen to 104 degrees or higher.

“The body will actually stop sweating,” Meyering said. “Muscles will really tend to kind of seize up and break down in the bloodstream.”

At that point, a person can become confused or disoriented, they can have seizures, or they can go into a coma, Meyering said.

Normally, the body’s temperature is regulated by a part of the brain called the hypothalamus, which works like an internal thermostat. But when the body’s core temperature rises to about 104, that internal thermostat stops working. The body is no longer able to sweat, which is the body’s main mechanism for cooling itself.

People experiencing heat stroke won’t be sweaty. Instead, “they’ll be hot and they’ll be dry,” said Matt Zavadsky, the chief transformation officer for MedStar. MedStar has already transported about 325 people to hospitals for heat-related illnesses so far this summer, an increase of 116.7% compared to the same time frame last year.

When the body experiences heat stroke, it starts a domino effect of other problems in the body, said Meyering, the ER doctor. The heat causes muscles to break down in the bloodstream, which can in turn lead to kidney failure.

The treatment for heat stroke is simple: Get the body’s core temperature back down to a normal range. To do that, ER physicians will start by simply putting the overheated person in an ice bath. In 2020, when a deadly heat wave killed hundreds of people in the Pacific Northwest, local emergency rooms filled body bags with ice and for patients experiencing heat stroke.

In extreme cases, Meyering said, he and his colleagues will put a catheter in the bladder or into the chest to circulate cold water around the body’s vital organs.

For Simmons, the construction worker, those interventions came too late. Emergency responders rushed to cool his body after Simmons’ coworker called 911, but Simmons’ core body temperature had risen too high to save him. Simmons’ death was one of hundreds of deaths identified in an investigation from Columbia Journalism Investigations, KERA, Public Health Watch, and other newsrooms who investigated workers who died while toiling outdoors in extreme heat, and the dearth of federal regulations that could have protected them. Last year, Simmons’ family settled a lawsuit against the construction company Simmons worked for. The company, Hellas Construction, agreed to pay $950,000, according to court records.

Simmons died from heat stroke, which alone kills more than any other weather-related event in the U.S.

The exact number of people who die because of high temperatures in Texas is unknown.

Heat stroke is frequently a cause of death for people who labor outside in extreme temperatures, for people who are trapped in hot cars, and for people who are homeless and get no reprieve from the heat. But heat can also exacerbate existing conditions and trigger other events in the body that can kill you. When the body’s core temperature rises, the body’s main cooling mechanisms are sweating more and increasing blood flow to your skin, which requires the heart to beat faster. Because of the physiological responses that are required of the body when temperatures rise, heat puts an immense strain on the heart, which can lead to death in cases where someone already has heart problems or cardiovascular disease.

The number of people killed by heat each year is an undercount, experts said, because that number usually only reflects the number of people killed by heat stroke, and not the people with other causes of death that were triggered by the heat.

“If the person had a heart attack, that’s what goes on the death certificate, even if the heart attack was caused by heat,” said Andrew Dessler, a professor of atmospheric sciences at Texas A&M University. “It’s really hard to get accurate tracking.”

Because it’s hard to precisely pinpoint how many people are killed by heat in Texas each year, future forecasts are similarly difficult to nail down.

But climate and health experts are confident that as summers get longer and hotter, and heat waves get more intense, more people will die preventable deaths.

Most of those deaths will likely be concentrated in northern states, where fewer homes and businesses have air conditioning, Dessler said. In a city like Chicago, he said, the first line of adapting to hotter temperatures will be adding air conditioning to indoor spaces.

“The places that are going to suffer most are places in the north,” Dessler said. “For a place like Texas, almost everyone already has air conditioning. And so then the question about large scale adaption is going to require things like changing building codes. It’s much less on individuals and more about government policy.”