A powerful heat wave hit the United States on Thursday, July 24, causing delays in more than 4,300 flights across major airports nationwide, according to data from FlightAware. Temperatures soared above 115°F (46°C) in several regions, forcing operational adjustments at airports like Chicago O’Hare, Dallas–Fort Worth, Hartsfield–Jackson Atlanta, Denver, Boston Logan, and Newark Liberty, among others.
Weather-related disruptions affected both ground operations and takeoff maneuvers. The National Weather Service warned that the Southeast, Midwest, and Tennessee Valley would face extreme conditions through at least Wednesday. Experts also noted that hot air is less dense, requiring longer runway distances for takeoff, while engines produce less thrust, resulting in longer ascent and landing times.
Among the most affected airlines were Southwest Airlines with 835 delayed flights, followed by American Airlines (536), United (385), and Delta (367). This created a domino effect—an early delay in one city disrupted schedules at connecting hubs nationwide.
Were passengers at risk during the affected flights?
According to aviation specialists in the United States, there was no direct threat to passenger safety during recent flights. However, prolonged ground delays in extreme heat can increase the risk of heat exhaustion, cabin discomfort, and unexpected cancellations.
The FAA estimates that around 74% of flight delays in the United States are weather-related. Experts recommend booking early morning flights during the summer, when temperatures are milder and the chance of disruptions is lower.