Best time to fly Minneapolis to Portland

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

Best month

September

95.3% on time · 127 flights

Worst month

December

48.3% on time · 119 flights

Month Flights On time Cancelled When late, by
January 83 68.3% 1.2% 60 min
February 78 73.1% 0% 40 min
March 102 73.7% 2.94% 46 min
April 117 94% 0% 101 min
May 141 91.5% 0% 65 min
June 163 84% 0.61% 48 min
July 150 74% 0% 53 min
August 138 91.3% 0% 68 min
September 127 95.3% 0% 26 min
October 151 86% 0.66% 58 min
November 143 85.3% 0% 39 min
December 119 48.3% 2.52% 53 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.