Best time to fly Anchorage to Chicago

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

Best month

January

100% on time · 5 flights

Worst month

March

61.5% on time · 27 flights

Month Flights On time Cancelled When late, by
January 5 100% 0%
March 27 61.5% 3.7% 148 min
April 31 86.7% 0% 114 min
May 93 81.3% 2.15% 50 min
June 141 73.4% 0.71% 56 min
July 155 75% 0.65% 47 min
August 143 72.5% 0.7% 54 min
September 100 88% 0% 34 min
October 48 80.4% 4.17% 40 min
November 29 70.4% 6.9% 50 min
December 15 86.7% 0% 29 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.