Best time to fly Atlanta to Boise

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

Best month

January

90.6% on time · 69 flights

Worst month

March

67% on time · 93 flights

Month Flights On time Cancelled When late, by
January 69 90.6% 5.8% 83 min
February 56 89.3% 0% 64 min
March 93 67% 2.15% 53 min
April 98 79.6% 0% 46 min
May 100 80% 0% 77 min
June 102 85.1% 0.98% 64 min
July 101 69.8% 4.95% 62 min
August 93 83.9% 0% 38 min
September 87 87.4% 0% 41 min
October 92 90.1% 1.09% 43 min
November 89 80.5% 1.12% 35 min
December 85 75% 1.18% 39 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.