Best time to fly San Juan to Dallas/Fort Worth

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

Best month

February

85.1% on time · 150 flights

Worst month

January

60.1% on time · 178 flights

Month Flights On time Cancelled When late, by
January 178 60.1% 9.55% 73 min
February 150 85.1% 0% 36 min
March 218 79% 1.83% 82 min
April 196 80.5% 0.51% 56 min
May 182 79.9% 0% 55 min
June 159 84.3% 0% 71 min
July 218 81.6% 1.38% 79 min
August 142 66.9% 0.7% 85 min
September 80 85% 0% 90 min
October 96 75.8% 0% 181 min
November 152 82.8% 0% 54 min
December 229 79.9% 0.44% 70 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.