Flagstaff Snowfall Totals & Accumulation Averages
This page pulls together information on when, how much and how often Flagstaff, Arizona has snow.
There are data and descriptions here of how many days it snows and the total amount of snowfall that Flagstaff usually gets.
There are also monthly and yearly counts of the days that the city normally has heavy snowstorms and deep snow accumulated on the ground. Plus there's information on when Flagstaff can expect the first and last snowfalls of the season.
All the numbers are averages, based on weather data gathered from 1991 to 2020 at the Flagstaff Pulliam Airport.
How Often it Snows in Flagstaff
This first table lists monthly and yearly totals for amount of snow and how many days it snows at least 0.1 inches (0.25 centimetres).
These averages don't show how much the snowfall in Flagstaff varies from year to year.
In December, for instance, one in four years totals over 27 inches of snow. Another 25 percent of years receive less than 9.3 inches for the month.
Similarly in January, fresh snowfall in the heaviest years amounts to over 34.3 inches, while the lightest years get less than 4.3 inches.
New snow for February ranges from over 25.4 inches in heavy snowfall years to just nine inches at most in light years.
When Flagstaff Has Its First & Last Snowfalls
The first snowfall of winter for Flagstaff can arrive as early as October or as late as December. About one in four Octobers get a light snow. But one in four Novembers don't see any fresh snow.
The season's last snowfall typically happens in April. About half of years also get a little snow in May.
Flagstaff is normally free of snow every year from June to September.
How Many Snowstorms Flagstaff Gets
Most days of snowfall in Flagstaff leave at least an inch of fresh snow on the ground. For 11 days a year on average, the amount of new snow totals at three inches or more.
Snowstorms of over five inches a day normally occur six times a year. Major blizzards that dump ten inches or more in one day typically show up once or twice a year. Storms this severe can descend on Flagstaff anytime from November to March.
How Much Snow Normally Accumulates in Flagstaff
For well over half of winter, Flagstaff has at least an inch of snow on the ground.
Snow mostly accumulates during January and February. Typically, on seven days in January and another four in February, the snow covering Flagstaff gets to ten or more inches deep. But only an average of two or three days a year see snow pile up to over 20 inches.
NOAA National Centers for Environmental Information (NCEI). Climate Normals.