Winter storm Ethan is threatening widespread flight delays throughout the US midwest and east coast, with weather advisories and storm warnings stretching from Illinois to New England. The storm could cause flight delays for last-minute holiday travel around Christmas.
But if history is any indication, summer is just as bad as winter when it comes to air-travel delays.
Where delays in winter months can vary from year to year, summer-time delays are more consistent. Weather is just one factor, causing delays just 3% or 4% of the time.
Furthermore, when it comes to weather delays, December is less troublesome than June.
Irrespective of the weather, more of the summer delays are caused by late-arriving aircraft, which is largely caused by more people flying. Summer is the most popular time to fly in the US, which means everything takes longer, from boarding to preparing for takeoff on the tarmac.