Health officials in North Carolina were worried that the National Weather Service was warning people about extreme heat dangers after temperatures had already skyrocketed “way too high.”
So, they wrote their own rules — challenging what some critics say are outdated federal policies in an age of sweltering heat waves that kill thousands of people every year. Now, the state sends out some heat alerts when temperatures are nearly 20 degrees lower than when NWS advisories are issued.
But those alerts could stop in September, during a summer when the state has experienced record levels of heat illnesses.
A federal grant that funds the alert system — overseen by a three-person team at the North Carolina Department of Health — is expected to end later this month, more than a year early. It’s part of President Donald Trump’s efforts to eliminate climate funding across the government, including for the Centers for Disease Control and Prevention, which provided the grant.
It’s just one example of how Trump’s approach to slashing spending and reducing the federal workforce has collided with a burgeoning effort to prevent heat-related deaths — often by warning people earlier.
The Trump administration is promoting policies to increase fossil fuel production at a time when global temperatures have reached levels that have never before been recorded by people. At the same time, the president has reduced support for communities that are trying to adapt to intensifying heat dangers.
In Texas and Florida cities, efforts to get residents to take the threat of heat more seriously have run up against staffing shortages at the National Weather Service and CDC.
“The real risk right now is there have been so many cuts at CDC that you don’t have the support to look at health effects,” said Juli Trtanj, who led the National Integrated Heat Health Information System at NOAA before leaving the agency this spring. “The weather service has been cut so much that the forecast offices don’t have the capacity to even engage in the heat conversation because they just have to get the forecast out.”
The National Weather Service did not respond to requests for comment. CDC did not respond to detailed questions about whether it would fulfill its five-year climate grants, saying only that the fiscal 2026 appropriations process “has not concluded.”
‘Really annoyed’
Heat is the top weather-related killer in the United States, contributing to at least 2,300 deaths annually, according to the CDC. But its health dangers only recently became a focus of climate adaptation efforts, as local officials and federal health experts recognized that what was once thought of as an uncomfortable inconvenience is actually a mass casualty risk. Heat can harm kidney function, exacerbate cardiac conditions and kill people.
Just as NWS does with tornadoes and flash floods, the agency issues localized heat alerts. They are usually based on regional temperature thresholds, often designated decades ago without accounting for human health impacts.
Emergency planners and hospitals often rely on the alerts to decide when to initiate interventions, like opening cooling centers or reducing outside activities for kids.
“A lot of local health people won’t do anything unless there is an official alert,” said a CDC official who was granted anonymity to speak about internal discussions. “But the NWS thresholds, they are set by small offices that are often not informed by when you’ll start seeing health effects.”
That was apparent in Chicago after a 1995 heat wave killed more than 700 people. Afterward, city officials worked with the local NWS office to change its criteria for when heat watches and warnings would be issued.
But local health departments have only recently begun to petition NWS to lower heat thresholds before mass-casualty events. Alerts go out at lower temperatures in New York City, areas of upstate New York and some New England states, usually with funding from the CDC’s program.
Many of those changes happened with the help of NIHHIS, a federal partnership begun at the end of the Obama administration to bring together heat experts across the federal government to address health dangers.
“The public health community was really annoyed because the heat thresholds were not actually helping people, and the NWS was constrained because their primary objective is getting a forecast out,” Trtanj said. “NIHHIS created the opportunity for NWS to have these deeper engagements with the health sector, with the communities, than they otherwise would have.”
Miami is a leader when it comes to modern heat alerts. Consistently ranked among the country’s hottest cities, Miami-Dade County established a task force in 2021 to develop an extreme heat action plan. It hired the nation’s first chief heat officer, Jane Gilbert.
Under her supervision, the task force made an alarming discovery. The local NWS office’s threshold was so high — a blistering 113 degrees Fahrenheit — that it had never issued a heat warning at all.
At the same time, the county was coming to grips with the human toll of high temperatures. A 2023 study by Florida State University geographer Christopher Uejio estimated that more than 600 heat-related deaths may occur across the county each year.
Officials in NWS’ national headquarters organized a pilot project that same year to support local and state heat initiatives in Miami, as well as Phoenix, Las Vegas and Charleston, South Carolina. The program included interactive tabletop exercises designed to help local officials improve their heat action plans.
“It was a great way to get the right people in the room,” said Gilbert, who recently stepped down from her role as Miami’s chief heat officer. Local NWS officials and emergency responders attended the exercise, along with national staff members from NOAA, including Trtanj, to provide guidance.
Around the same time, the county worked with the local NWS office to lower its warning thresholds. Now, forecasters issue heat watches at 105 F and heat warnings at 110 F.
Miami’s story isn’t unique.
Other NWS offices across the country have begun to reevaluate heat warnings, incorporating new research suggesting that danger to human health can occur at much lower temperatures than scientists previously thought.
At 105 degrees, illness is ‘almost guaranteed’
Four NWS offices in Oklahoma and Texas decided last year to change their criteria after a study found that their thresholds were so high they rarely ever resulted in excessive heat warnings.
Forecasters in Amarillo, Texas, hope the new standards will save lives when hikers descend on nearby Palo Duro Canyon State Park. The office has set its new threshold for heat advisories at a heat index of 105 F.
“Once we start hitting that, it’s almost guaranteed that you’re gonna start seeing several instances of heat illness,” said Aaron Ward, the science and operations officer at NWS Amarillo. “And we’ve had several fatalities out there as well.”
Some offices aren’t stopping there. Studies suggest that health risks can occur at much lower temperatures than the thresholds that trigger heat warnings.
The NWS office in Columbia, South Carolina, lowered its warning threshold last year. But it has also launched an experimental program designed to communicate heat risks to the public in more useful ways.
In addition to the heat index, which triggers heat warnings, the meteorologists calculate daily wet bulb temperature, a health-related metric based on temperature and humidity. They also estimate risks using the HeatRisk tool, a color-coded system created by NOAA and CDC scientists to assess daily heat threats to human health across the country.
Each day, NWS Columbia summarizes all of these metrics in a report and sends it to local partners, like hospitals and emergency managers.
Because South Carolina is among the country’s fastest growing states, Frank Alsheimer, the science and operations officer at NWS Columbia, worries that new residents from cooler places might not know the dangers of local heat. He hopes the new program will make a difference — and potentially save lives.
“We need to make sure that our messaging is not just for people who have been here forever,” he said. “But also people who are new and moving in and may not realize the true danger that heat can be to health.”
‘We don’t have the manpower’
Better heat alerts are a start — but many groups still aren’t sure how well their efforts are paying off. Tracking heat-related hospitalizations and deaths takes time, money and dedicated staff.
The Trump administration’s budget cuts, which have slashed NWS staff and frozen or eliminated grants for climate-related research, aren’t helping.
Meteorologists at NWS Amarillo had hoped to track the results of their new warning thresholds by working with local hospitals and rangers at Palo Duro Canyon.
But staffing shortages are thwarting their plans. As of June, the office was down from a staff of 13 meteorologists to nine and was struggling to cover overnight shifts.
“Until things get better, unfortunately we just don’t have the manpower and the time,” said Ward, the office’s science and operations officer.
In North Carolina, CDC funds helped state experts develop an alert system for the state. Temperature thresholds for alerts are different at the start, middle and end of summer, and vary across eight regions. In early summer, alerts for the western region of the state are sent when the heat index is forecast for 85 F. NWS doesn’t set heat alerts until the index reaches 105 F.
“We want to be sending out heat alerts when the forecast looks like it will be at an unhealthy level, not once it is already there,” said Autumn Locklear, a climate and health epidemiologist who worked on the thresholds.
State analyses have shown that emergency department visits for heat decreased in the first year after the state began issuing them.
Without CDC funds, Locklear’s three-person team will be out of work in September, and the North Carolina alert program will stop before the heat season is over. Emergency departments across the state saw more than 3,300 heat-related visits from May to July, a new record, according to the state Department of Health.
The entire climate and health staff at the CDC was placed on administrative leave for two months in the spring. That shuttered online tools that showed in real time how high temperatures were increasing hospital visits. The tool was down for months, including during a heat dome in June.
CDC climate staff are now back at work, but Trump has asked Congress to zero out the program’s budget in its next spending bill. That means the climate office could be defunded by Oct. 1.
If that happens, there may be no one in the federal government who can help state and local officials prevent heat illness.
NIHHIS has also been hampered by staffing cuts.
The heat-related tabletop exercises in Miami and other communities in 2023 stemmed from a partnership between NOAA and NIHHIS. In January, as the Biden administration was preparing to exit, NOAA and NIHHIS announced funding awards for tabletop exercises in 10 more communities, from California to Puerto Rico.
Those awards were disbursed, according to NOAA. But the funding was provided by the 2022 Inflation Reduction Act, and there are no plans for another award cycle.
“The thing is, there is no requirement anywhere to make sure that heat wave warnings include health data, and there’s no money specifically for it, it’s just something that can be done if you have the right people in the same room having the conversation,” the CDC official said. “But the people who are still here could be losing their jobs by the fall.”
