Best time to fly Butte to Salt Lake City

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

Best month

October

98.9% on time · 88 flights

Worst month

July

89.2% on time · 93 flights

Month Flights On time Cancelled When late, by
January 59 96.6% 0% 32 min
February 52 96.1% 1.92% 95 min
March 57 94.7% 0% 119 min
April 56 94.4% 3.57% 84 min
May 61 95% 0% 160 min
June 60 95% 0% 436 min
July 93 89.2% 0% 66 min
August 93 97.8% 0% 49 min
September 88 94.3% 0% 218 min
October 88 98.9% 0% 137 min
November 85 94% 1.18% 32 min
December 87 94.3% 0% 491 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.