Vastavam web: We heard that flights are cancelled due to fog, heavy down pour or dust released by burning volcano but we never listen that flight services are stalled due to extraordinary temperature large number of flights services are cancelled in USA. As the US National Weather Service warns of “excessive heat” across the south-western states, dozens of flights have been cancelled due to excessive temperatures. Afternoon temperatures in the Arizona state capital, Phoenix, are expected to reach 120F (49C) in what local media has called a “hellscape” heatwave. At the city’s Sky Harbor airport, one of the 10 busiest in the US, dozens of flights have been cancelled because of the predicted heat. High temperatures make the air thinner, reducing lift and impairing an aircraft’s performance. Many American Airlines’ regional services use Canadian-build Bombardier CRJ aircraft, which are not certified to operate above 118F (48C). So the airline has pre-emptively cancelled around 50 flights that were due to be operated by Skywest and Compass airlines under the American Eagle brand.