Best time to fly Spokane to Salt Lake City

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

Best month

April

94.6% on time · 298 flights

Worst month

August

81.1% on time · 277 flights

Month Flights On time Cancelled When late, by
January 243 89.6% 0.82% 80 min
February 212 86.7% 0% 95 min
March 289 90.2% 1.38% 56 min
April 298 94.6% 0% 75 min
May 299 90% 0% 73 min
June 290 90.7% 0.34% 102 min
July 291 81.6% 3.09% 128 min
August 277 81.1% 0.36% 85 min
September 276 90.9% 0% 128 min
October 292 91.4% 0.34% 69 min
November 263 91.2% 0.38% 91 min
December 294 87.7% 0.34% 58 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.