Best time to fly Denver to Kalispell

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

Best month

October

91.5% on time · 200 flights

Worst month

December

72.1% on time · 167 flights

Month Flights On time Cancelled When late, by
January 160 74.2% 1.88% 58 min
February 139 74.1% 0% 67 min
March 153 82.2% 0.65% 52 min
April 120 85.7% 0% 54 min
May 183 79.7% 0.55% 56 min
June 240 72.4% 0% 58 min
July 245 78.6% 0.82% 61 min
August 248 78.9% 0.4% 75 min
September 212 90.6% 0% 31 min
October 200 91.5% 0% 43 min
November 118 83.8% 0% 96 min
December 167 72.1% 0% 68 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.