Phoenix is no stranger to heat, but the sweltering temperatures have gotten so bad that it's making it tough for some people to leave.
Phoenix's airport canceled dozens of flights because it was just too hot. Temperatures hit 118 degrees, exceeding the maximum heat threshold for some smaller planes.
Higher temperatures make for thinner air, which is harder to generate lift from. Without the denser air pushing it upward, a plane's engines need to do more work to get it to takeoff speed.
Phoenix's summer temperatures are usually between 105 and 110 degrees, but this week they're closing in on 120 degrees, though they're not expected to break the all-time record of 122 degrees.
Phoenix is just one area suffering under a record heat wave. Other western U.S. cities like Sacramento and San Francisco have seen record-high temperatures this week.
