Best time to fly Rio de Janeiro to São Paulo

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

Best month

May

92.7% on time · 3,184 flights

Worst month

December

72.8% on time · 1,529 flights

Month Flights On time Cancelled When late, by
January 2,982 88.4% 4.09% 45 min
February 2,856 87.1% 3.82% 45 min
March 3,186 91.1% 2.51% 46 min
April 3,108 88.1% 4.28% 50 min
May 3,184 92.7% 2.1% 42 min
June 2,044 90.6% 2.98% 39 min
July 3,154 91.2% 5.07% 39 min
October 251 83.7% 1.99% 36 min
November 1,515 87.8% 2.38% 50 min
December 1,529 72.8% 7.06% 62 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.