Across the U.S. West Coast, an intense heat wave has shattered temperature records, led to widespread power outages and forced airlines to cancel flights. Last week, American Airlines canceled about 50 flights to and from Phoenix (PHX) as temperatures in Arizona climbed to extreme levels.
The cancellations primarily affected smaller regional jets that have lower maximum operating temperature limits compared with larger mainline aircraft produced by Boeing and Airbus. Those regional planes are unable to operate safely when ambient temperatures reach around 118 degrees Fahrenheit.
“Our smaller regional operations — those that use our CRJ aircraft types — will be most affected by the heat,” said Kent Powell, a communications specialist for American Airlines. “We really aren’t expecting any change to the operation with our mainline aircraft.”
To notify travelers in advance, the carrier announced it would ground certain regional flights during the heat wave when temperatures approached 120 degrees. American Airlines also waived change fees for affected passengers traveling through Phoenix to ease disruptions.
High temperatures reduce air density, which decreases wing lift and engine performance during takeoff. To compensate, airlines often restrict payloads by limiting passenger count or baggage weight, but when temperatures exceed a plane’s certified operating limits—around 118 degrees for some regional types—the only safe choice is to cancel or delay the flight.
Although cancellations caused by heat are still relatively uncommon, experts warn they could rise as global temperatures increase. A study by the University of Hawai‘i projects that, by 2100, roughly half of the world’s population may experience at least one month each year with dangerously high heat, increasing the likelihood of weather-related travel disruptions.
Last week’s excessive heat warnings covered inland areas of California, southern Nevada and parts of southwest Arizona. In California alone, more than 29 million residents were under a heat warning or advisory, underscoring the scale of the event and its potential to disrupt transportation and public services.