Best time to fly Spokane to Phoenix

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

Best month

September

94.9% on time · 156 flights

Worst month

December

80.3% on time · 228 flights

Month Flights On time Cancelled When late, by
January 227 81% 0.44% 86 min
February 211 88.2% 0% 48 min
March 252 83.9% 0.4% 77 min
April 242 87.1% 0.41% 158 min
May 216 87.4% 0.46% 40 min
June 201 85% 0.5% 49 min
July 186 83.9% 0% 99 min
August 196 89.8% 0% 80 min
September 156 94.9% 0% 220 min
October 183 85.2% 0% 135 min
November 212 85.4% 0% 76 min
December 228 80.3% 0% 74 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.