Best time to fly Fresno to Portland

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

Best month

November

97% on time · 33 flights

Worst month

January

82.8% on time · 31 flights

Month Flights On time Cancelled When late, by
January 31 82.8% 6.45% 66 min
February 28 96.3% 0% 97 min
March 31 90% 3.23% 21 min
April 39 92.3% 0% 150 min
May 43 85.7% 2.33% 202 min
June 51 92.2% 0% 86 min
July 102 90.2% 0% 52 min
August 93 92.5% 0% 57 min
September 86 95.3% 0% 124 min
October 43 88.4% 0% 46 min
November 33 97% 0% 16 min
December 47 85.1% 0% 45 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.