Best time to fly Charlotte to San Juan

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

Best month

February

85.2% on time · 212 flights

Worst month

July

51.8% on time · 168 flights

Month Flights On time Cancelled When late, by
January 231 76.5% 6.49% 70 min
February 212 85.2% 0.94% 57 min
March 260 81% 0.38% 75 min
April 201 71.6% 0% 45 min
May 193 76% 0% 47 min
June 152 70.3% 2.63% 101 min
July 168 51.8% 0% 112 min
August 140 56.6% 2.86% 75 min
September 72 79.2% 0% 86 min
October 119 67.2% 0% 40 min
November 171 84.2% 0% 56 min
December 246 80.9% 0% 47 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.