Best time to fly São Paulo to Mendoza

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

Best month

January

87.5% on time · 72 flights

Worst month

December

64.3% on time · 70 flights

Month Flights On time Cancelled When late, by
January 72 87.5% 0% 40 min
February 63 85.5% 1.59% 29 min
March 67 85.1% 0% 24 min
April 67 69.7% 1.49% 35 min
May 72 81.9% 0% 31 min
June 69 65.2% 0% 33 min
July 157 74.5% 0% 36 min
August 91 78% 0% 47 min
September 75 77.9% 9.33% 25 min
October 42 86.8% 9.52% 26 min
November 68 70.6% 0% 31 min
December 70 64.3% 0% 38 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.