Best time to fly Chicago to Lansing

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

Best month

October

85.5% on time · 62 flights

Worst month

January

53.3% on time · 60 flights

Month Flights On time Cancelled When late, by
January 60 53.3% 0% 82 min
February 53 75.5% 0% 58 min
March 58 72.2% 6.9% 69 min
April 59 77.8% 8.47% 63 min
May 62 75% 3.23% 46 min
June 60 81% 3.33% 91 min
July 91 68.9% 1.1% 57 min
August 90 80.7% 2.22% 52 min
September 61 85.2% 0% 32 min
October 62 85.5% 0% 48 min
November 59 71.4% 5.08% 47 min
December 62 59.3% 4.84% 62 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.