Phoenix Flights Grounded Because It's Literally Too Hot to Fly Planes

Temperatures expected to approach 120 degrees Fahrenheit; smaller regional jets cannot fly once temperatures hit 118 degrees

File photo: A jet seen through heat ripples as it lands at Phoenix's Sky Harbor International Airport.
File photo: A jet seen through heat ripples as it lands at Phoenix's Sky Harbor International Airport. Matt York/AP

Airlines canceled flights in Phoenix and doctors urged people to be careful around concrete, playground equipment and vehicle interiors Monday as a punishing heat wave threatens to bring temperatures approaching 120 degrees to parts of the Southwestern U.S.

American Airlines canceled nearly 40 flights on Tuesday in Phoenix operated by regional jets because of the heat. The airline also said it will allow Phoenix passengers flying during the peak heat Monday through Wednesday to change flights without a fee.

American Airlines spokesman Ross Feinstein said the smaller regional jets flown by its partners can’t operate once the temperature hits 118. That maximum is set by Bombardier, the manufacturer.

Larger airliners made by Boeing and Airbus have higher maximum operating temperatures, but airlines still need to closely monitor the weight of the jets during the heat.

Feinstein said the carrier began limiting sales on some flights to prevent the planes from exceeding maximum weight for safe takeoff in the hot conditions. Airlines can use other strategies for limiting weight during hot weather, such as not fueling completely, then making a refueling stop.

 A study in the journal Nature Climate Change published on Monday said that the number of extreme heat waves was expected to climb to affect half of the Earth's population by the year 2100.