Missoula Snowfall Totals & Accumulation Averages
This page pulls together information on when, how much and how often Missoula, Montana has snow.
There are data and descriptions here of how many days it snows and the total amount of snowfall that Missoula 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 Missoula can expect the first and last snowfalls of the season.
All the numbers are long-term historical averages based on weather data gathered from 1981 to 2010 at the Missoula International Airport.
How Often it Snows in Missoula
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 Missoula varies from year to year.
In December, for instance, one in four years totals over 13.2 inches of snow. Another 25 percent of years receive less than 6.3 inches for the month.
Similarly in January, fresh snowfall in the heaviest years amounts to over 9.5 inches, while the lightest years get less than four inches.
New snow for February ranges from over 9.3 inches in heavy snowfall years to under 2.5 inches in light years.
When Missoula Has Its First & Last Snowfalls
The first snowfall of winter for Missoula usually arrives in November. In one out of four years, October also gets some snow.
The snow season ends most often in April. About once every four years April has no snow, which moves the last snowfall to March. Snow can show up as late as June, but that is rare, historically occurring only about once a decade.
Missoula is normally free of snow each year from July to September.
How Many Snowstorms Missoula Gets
Two-thirds of the days with snowfall in Missoula amount to just a skiff, leaving less than an inch of fresh snow on the ground. For 13 days a year on average, the amount of new snow totals at least an inch.
Snowstorms of over five inches a day don't occur every year. Major blizzards that dump ten inches or more in one day are not expected here.
How Much Snow Normally Accumulates in Missoula
For about half of winter days, Missoula has at least an inch of snow on the ground.
Snow mainly accumulates during January, the month when the snowpack is most likely to top ten inches. Typically on eight days in January and another three to five in December and in February, the snow covering Missoula gets to five or more inches deep.
National Climatic Data Center. NOAA's 1981-2010 Climate Normals.