Best time to fly Baltimore to Milwaukee

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

Best month

September

89% on time · 172 flights

Worst month

July

62.9% on time · 178 flights

Month Flights On time Cancelled When late, by
January 89 86.6% 7.87% 41 min
February 86 88.1% 2.33% 55 min
March 111 78.7% 2.7% 87 min
April 118 76.3% 0% 43 min
May 131 71.5% 0.76% 52 min
June 174 69.6% 1.15% 66 min
July 178 62.9% 0% 71 min
August 183 70.9% 1.64% 57 min
September 172 89% 0% 44 min
October 177 83.5% 0.56% 45 min
November 147 80.8% 0.68% 49 min
December 148 69.2% 1.35% 40 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.