Best time to fly Chicago to Idaho Falls

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

There is not yet enough of the year on record for this route to say anything about seasons. The months below are shown as recorded.

Month Flights On time Cancelled When late, by
May 13 84.6% 0% 138 min
June 34 58.8% 0% 45 min
August 26 50% 0% 64 min
September 30 72.4% 3.33% 54 min
October 31 35.5% 0% 58 min
November 1 100% 0%

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.