Best time to fly Rapid City to Chicago

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

Best month

January

100% on time · 5 flights

Worst month

March

50% on time · 2 flights

Month Flights On time Cancelled When late, by
January 5 100% 0%
March 2 50% 0% 232 min
April 71 64.7% 4.23% 86 min
May 104 78.2% 1.92% 69 min
June 120 73.9% 0.83% 162 min
July 121 64.1% 1.65% 70 min
August 109 61.5% 1.83% 56 min
September 74 83.6% 1.35% 60 min
October 38 81.6% 0% 32 min
November 30 79.3% 3.33% 42 min
December 15 80% 0% 153 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.