Bureau of Transportation Statistics (BTS) records confirm that Miami International Airport (MIA) posts a 75.6% year-round on-time arrival rate, with cancellations averaging 1.4%. When irregular operations strike, delayed passengers wait an average of 77 minutes. System reliability shifts dramatically depending on the calendar: October ranks as MIA’s best month, logging an 83.7% on-time performance as stable fall conditions take hold across the South Florida basin.
Summer convective activity causes operational integrity to drop significantly. Between June and September, high-top afternoon thunderstorms reliably park over terminal airspace, forcing FAA ground stops and extensive route diversions. July marks the annual low point, with on-time performance sinking to 67.1%. MIA’s status as a dominant international gateway compounds these weather delays; handling complex widebody staging, extended customs holds, and longer taxi times prevents carriers from recovering lost time as quickly as domestic-focused hubs.