Best time to fly Minneapolis to St. Louis

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

Best month

September

88.1% on time · 336 flights

Worst month

July

66% on time · 319 flights

Month Flights On time Cancelled When late, by
January 295 81% 2.71% 72 min
February 294 85.6% 0.68% 66 min
March 356 79.3% 2.25% 84 min
April 334 84.1% 0% 54 min
May 317 87.6% 0% 81 min
June 309 73.9% 0.97% 64 min
July 319 66% 2.82% 68 min
August 332 80.4% 0% 59 min
September 336 88.1% 0% 56 min
October 315 87.5% 1.27% 66 min
November 293 84% 0% 57 min
December 315 73.6% 1.27% 75 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.