A heat dome is locking in high temperatures across the country heading into the Fourth of July.
The wave spans from the Central U.S. to the East Coast through the weekend with afternoon temperatures in the 90s and 100s.
Peak heat for the U.S. is hitting Thursday when 70% of the country — about 239 million people — will experience forecast highs of 90 degrees or more, and 37 million possibly seeing highs above 100 on Friday.
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The biggest climate impacts are expected for states like Indiana, Tennessee, Kentucky, West Virginia, Virginia, Pennsylvania, Delaware, and New Jersey.
Meteorologist Shel Winkley with Climate Central said Florida's peak heat is forecast for Friday with feel-like temps in the triple digits.
“Heatwaves are common in the summer months. That is not new. But with climate change, these are not the heatwaves of decades past,” he said via email. “They are now more intense, longer lasting, and becoming more frequent during the summer months.”
He said 75% of Florida, or 17.6 million residents, will experience heat made at least three times more likely by human-caused climate change.
How to prep for extreme heat
Cheryl Holder, a doctor and founder of Florida Clinicians for Climate Action, said people aren’t built to endure triple digit highs.
"Physiologically, I don't care how healthy you are, your body is not designed to really maintain that and give the own cooling. You have to help the body," Holder said.
Help your body by staying hydrated, wearing light clothing, she said, and stopping what you're doing if you feel cramping, nausea, or weakness.
Some of the most vulnerable to heat illness are the pregnant or elderly.
“Heat itself is what we call a threat multiplier, so especially in Florida, where we have more elderly people, so you have diabetes, then you have all these additional hot days that worsens hydration, increases the sugar, worsens the kidney function,” she said.
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“We see it with pregnant women who may be already on the edge.”
Holder is training Florida doulas on heat education and care. One birth worker she spoke to recently had a patient living in a hot RV go into pre-term labor.
“Despite everything she did: walking around in her shorts and hydrating, she still went into labor a few weeks early. She just couldn't keep up,” Holder said.
It's been two years since Florida banned local governments from setting heat protections for another vulnerable population: outdoor workers.
Holder said she's looking for the long-term health effects of the state’s decision.
"What we will monitor is a chronic level of dehydration on the kidneys. Does that mean that in 5,10 years, like what we saw in the farms in Nicaragua and other places in Central America, worsening of kidney function and chronic kidney disease?" she asked.
For now, she said, her organization will continue informing clinicians and politicians about heat illness.
Working in triple digit temps
Anthony Cantu has been a UPS delivery driver in Tampa for about 15 years, so he's no stranger to working in his vehicle with triple digit temperatures in the back cargo area.
"The heat can catch up on you really quickly. I noticed, like, a lot of fatigue, especially when I get to that, like, 3 o'clock, 4 o'clock hour," he said.
But he takes a lot of personal precautions, like drinking 1 liter of water per hour, and eating clean, including hydrating fruits.
"I try to eat a lot of melon, try to eat cucumbers, lettuce, strawberries, whatnot, and try to replenish with like electrolyte packets every two to three hours or so," Cantu said.
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Cantu said this year's drought has been taking a toll on him since he's used to relying on the summer afternoon showers to cool off.
"So the cargo area, where the packages sit, the temperatures can get as hot as like 130, 140 degrees," he said.
His job does provide some heat safety measures, like fans, access to ice cold water and breaks.
But he'd still like to see shorter work weeks and air conditioning in both the cab and cargo of his work vehicle.
"I think that all workers deserve dignity and respect and ... In the end, it's more important to prioritize people over company profits," Cantu said.
