Best time to fly São Paulo to Dallas/Fort Worth

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full GRU to DFW record →

Best month

August

91.9% on time · 62 flights

Worst month

December

73.8% on time · 68 flights

Month Flights On time Cancelled When late, by
January 76 85.9% 6.58% 344 min
February 60 78.3% 0% 160 min
March 63 77.8% 0% 132 min
April 60 86% 5% 33 min
May 62 78.3% 3.23% 104 min
June 60 84.5% 3.33% 614 min
July 93 88% 1.08% 532 min
August 62 91.9% 0% 356 min
September 60 86% 5% 610 min
October 62 80.3% 1.61% 131 min
November 60 75% 6.67% 171 min
December 68 73.8% 4.41% 261 min

What a seasonal pattern can and cannot tell you

Months differ for reasons that repeat — summer thunderstorms in the American interior, winter fog and de-icing in northern Europe, school holidays filling every seat and leaving no slack in the schedule. Those are real and they come back each year.

What the pattern cannot do is forecast a particular flight. A quiet month has late days and a bad month has punctual ones. Treat this as a way to choose between two dates you are indifferent about, not as a promise.