Hot air is thinner, making it harder for planes to generate lift and thrust. This issue is significant for travellers as rising temperatures could lead to increased flight delays and cancellations, affecting travel plans and airport operations across Canada and beyond. Aircraft at higher elevations are already operating in thinner air, so temperatures don’t have to climb as high to affect takeoff performance. The following year, the airline canceled dozens of regional flights in Arizona as temperatures in Phoenix climbed toward 120 F (49 C). In July 2018, some airlines bumped passengers at Denver International Airport to later flights as temperatures reached 98 F (37 C), KDVR-TV in Denver reported.