Best time to fly San Diego to Detroit

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

Best month

October

93.2% on time · 118 flights

Worst month

March

76.9% on time · 93 flights

Month Flights On time Cancelled When late, by
January 94 89% 2.13% 35 min
February 84 88% 1.19% 65 min
March 93 76.9% 2.15% 40 min
April 106 89.6% 0% 71 min
May 112 91% 0.89% 26 min
June 105 86.7% 0% 61 min
July 133 80.3% 0.75% 45 min
August 131 79.1% 1.53% 32 min
September 119 86.3% 1.68% 59 min
October 118 93.2% 0% 42 min
November 107 84.1% 0% 66 min
December 112 87.2% 2.68% 69 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.