Scorching temperatures at airports across the American Southwest are forcing airlines to pull passengers off planes, cut cargo, and cancel flights entirely, a trend that research suggests will only get worse in the decades ahead.
On July 24, the thermometer at Harry Reid International Airport in Las Vegas hit 114°F. American Airlines responded by offering compensation to customers willing to give up their seats on a departing flight, a move the airline described as standard practice at hot-weather destinations. The physics are straightforward: hot air is thinner than cool air, which robs wings of lift and jet engines of thrust. When the numbers stop working, something has to come off the plane, bags, fuel, or people.
The incident was not an outlier. It was the latest in a growing pattern of heat-related flight disruptions that stretches back years and now touches some of the busiest airports in the country, the Associated Press reported. And the data show the problem is accelerating.
An AP analysis of weather station data paints a stark picture. Phoenix Sky Harbor International Airport has averaged 43 days per year since 2020 when the temperature reached at least 110°F. That figure has more than tripled compared to the middle of the last century, with the surge concentrated in the 2020s.
Las Vegas is on a similar track. Harry Reid International Airport averaged roughly 18 days per year above 110°F between 2020 and 2025, more than double the annual average recorded during the 1940s through 1960s.
Palm Springs International Airport in California may have it worst. The airport has logged an annual average of 55 days at or above 110°F this decade, an 83 percent increase over the 2000s, when the weather station first began recording data.
Those numbers matter because pilots and airlines run weight-and-balance calculations before every departure. They factor in runway length, airport elevation, and outside temperature. When the heat spikes, the math tightens. Airlines may have to reduce cargo, carry less fuel, or ask passengers to step aside.
Ross Aimer, a retired United Airlines captain and CEO of Aero Consulting Experts, put it bluntly:
"At some point, the numbers just don't make sense. You could roll down a runway as long as you want, and you still can't take off."
Aimer compared jet engines in extreme heat to athletes competing at high altitude, where thin air saps performance. The analogy is apt, Mexico City, sitting more than 7,300 feet above sea level, has long been notorious for exactly that effect during international soccer tournaments.
The disruptions are not hypothetical. They have a documented track record. In June 2016, American Airlines canceled several round-trip regional flights between Palm Springs and Phoenix during a brutal heat stretch. The following year, the airline canceled dozens of regional flights across Arizona as temperatures in Phoenix climbed toward 120°F.
In July 2018, airlines bumped passengers at Denver International Airport to later flights when temperatures reached 98°F. Denver sits more than 5,000 feet above sea level, which compounds the thin-air problem even at temperatures that would be manageable at a sea-level airport.
Weather is far from the only threat to smooth air travel. Tropical storms have snarled flights at California airports, and infrastructure failures add another layer of unpredictability for travelers already dealing with crowded skies.
Then there was the July 2023 incident in Las Vegas. Delta Air Lines asked passengers to volunteer to leave a plane during an excessive heat warning because of weight restrictions tied to extreme temperatures. No one got off fast enough. The flight was ultimately canceled, and passengers spent hours aboard the aircraft in the heat.
Retired Delta captain Alan Price explained that airports with shorter runways face the problem sooner. He pointed to LaGuardia Airport in New York and Reagan National Airport in Washington as examples of facilities more likely to hit takeoff restrictions or weight limits during very hot weather. Shorter runways leave less room for error when an overheated engine cannot produce full thrust.
LaGuardia has dealt with its own infrastructure headaches beyond heat. A runway sinkhole at LaGuardia recently triggered hours of flight chaos, a reminder that aging airport facilities compound weather-driven disruptions.
A 2017 study by researchers from Columbia University, NASA's Goddard Institute for Space Studies, and the Logistics Management Institute examined 19 airports worldwide. Their finding: some airports could face weight restrictions on 10 to 30 percent of flights departing during the hottest part of the day by midcentury, assuming greenhouse gas emissions continued to rise.
A more recent study pushed the projections further. Current climate models indicated that planes taking off from four European airports would need to shed the weight equivalent of 10 passengers per flight by 2065. The study's authors were not identified in the AP's reporting, and the specific airports were not named.
The Federal Aviation Administration does not set a single maximum temperature for takeoff. Operating limits vary by aircraft make and model, weight, and airport altitude. That means there is no universal red line, each flight's go/no-go decision depends on a combination of factors that shifts with every degree on the thermometer.
Aimer framed the core issue as non-negotiable physics:
"There is a science behind all this. You can't deny the science of flight and what it takes for an airplane to operate."
He added a comparison that any traveler can grasp:
"Just like human beings, jet engines require lots of cool, dense air to perform well."
Jennifer Brady, a data scientist at Climate Central, noted that airports are especially vulnerable to the urban heat island effect. Vast expanses of asphalt and concrete, minimal shade, and constant engine exhaust create conditions that push temperatures higher than surrounding areas.
Brady said airports concentrate every ingredient for extreme surface heat:
"All of the elements are there for it being one of the hottest spaces in a city."
That means the temperatures pilots use in their takeoff calculations are often hotter than what residents experience a few miles away. An airport thermometer reading 114°F is not an abstraction, it is the number that determines whether a plane full of passengers can safely leave the ground.
Commercial aviation faces safety questions from multiple directions. A firework recently struck a Delta jet descending into Chicago Midway, drawing an FBI investigation and raising concerns about hazards that have nothing to do with weather.
Without a uniform FAA temperature limit, the burden falls on individual airlines and flight crews to decide when conditions cross the line. American Airlines has called weight reduction a standard industry practice. But for the passenger who bought a ticket, packed a bag, and showed up at the gate, being told the plane is too heavy to fly feels like anything but standard.
The open questions are significant. The AP's reporting does not say whether all passengers on the July 24 Las Vegas flight ultimately traveled that day, what specific compensation American offered, or whether the flight departed on time after adjustments. Those details matter to the travelers who bore the consequences.
And the broader aviation system faces challenges well beyond heat. An Air Canada captain allegedly flew 900 flights over 17 years without a required pilot license, a case that underscores how regulatory gaps can persist for years before anyone notices.
The data point in one direction. Extreme-heat days at major airports are multiplying. The physics of flight have not changed. And the federal government has declined to set a clear standard, leaving passengers to absorb the fallout one canceled flight at a time.
When the runway turns into a frying pan, the laws of physics do not negotiate, and neither should the people responsible for keeping travelers informed about what that means for their plans.
