Best time to fly Baltimore to Louisville

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

Best month

February

96.4% on time · 56 flights

Worst month

July

57.5% on time · 81 flights

Month Flights On time Cancelled When late, by
January 63 84.7% 6.35% 60 min
February 56 96.4% 1.79% 88 min
March 62 85.2% 1.61% 61 min
April 74 75.7% 0% 51 min
May 80 70% 0% 44 min
June 81 73.8% 1.23% 60 min
July 81 57.5% 9.88% 76 min
August 80 79.7% 1.25% 47 min
September 77 88.3% 0% 35 min
October 95 78.9% 0% 46 min
November 73 83.8% 6.85% 33 min
December 66 80% 1.52% 50 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.