Home › Montana › Great Falls

When does it first snow in Great Falls, MT?

At Great Falls, the typical date of the first measurable snowfall (0.1 inch or more in a day) is Oct 11. That is the median over the last 30 snow seasons: half of seasons saw it earlier, half later. In about 1 season in 10 it came by Sep 27, and in 1 in 10 not until Oct 29 or later. The earliest was Sep 16 (2006-07) and the latest Nov 5 (2024-25). A first snowfall of at least 1 inch in a single day typically arrives around Oct 19, and 100% of seasons had one. The first freeze of fall (a low of 32°F or colder) typically comes around Sep 21, and the last freeze of spring around May 22.

This season so far (2026-27, data through Oct 16, 2026): first measurable snow Oct 10; first freeze (32°F or colder) Sep 27 at this station. Compare with the typical dates above. This is observed data and can lag by a day or two, and it is not a forecast.

Oct 11Median first measurable snow (0.1"+)

Oct 19Median first 1"+ snowfall

66.9"Average snowfall per season

43%Chance of white Christmas (1"+ on ground Dec 25)

Sep 21Median first fall freeze (≤32°F)

May 22Median last spring freeze (≤32°F)

124Median freeze-free days between

First snowfall dates at Great Falls

First day with…	Median date	Typical range (10th–90th pct)	Earliest in 30 seasons	Latest in 30 seasons	Seasons with one
0.1" of snow or more (measurable)	Oct 11	Sep 27 – Oct 29	Sep 16 (2006-07)	Nov 5 (2024-25)	100%
1" of snow or more	Oct 19	Oct 2 – Nov 16	Sep 16 (2006-07)	Nov 23 (2021-22)	100%
3" of snow or more	Nov 16	Oct 17 – Jan 18	Sep 28 (2019-20)	Feb 14 (1999-00)	100%

Based on 30 seasons (July–June, 1995-96 to 2024-25) with at least 85% complete daily snowfall records at the station. Dates are for a single day’s snowfall, so "1 inch" means one calendar day with 1" or more, not total accumulation.

Chance the first snow has already happened by a given date

Snowfall	By Nov 1	By Dec 1	By Jan 1
0.1"+ (measurable)	93%	100%	100%
1"+	77%	100%	100%

In spring, the last measurable snowfall of the season typically falls around May 11 (median).

White Christmas odds in Great Falls

NOAA defines a white Christmas as at least 1 inch of snow on the ground on the morning of December 25. Using the last 30 years of daily snow-depth records (1995–2024) at this station, Great Falls had that in 43% of years, at least 3 inches in 33%, and at least 6 inches in 3%. The average depth on Dec 25 was 1.5 inches and the deepest was 7 inches. New snow was falling (0.1" or more) on Christmas Day itself in 23% of years. Based on 30 years with a recorded depth on Dec 25.

Chance of at least 1 inch of snow on the ground, by date

Share of the last 30 years with 1"+ snow depth within 3 days of each date. Snow cover is most likely around Jan 2 (52%). Red line: Dec 25.

First and last freeze dates in Great Falls

Threshold	Event	Median date	Typical range (10th–90th pct)	Earliest / latest	Years with one
32°F or colder (freeze)	First in fall	Sep 21	Sep 12 – Oct 4	Sep 8 (2020) / Oct 13 (2022)	100%
32°F or colder (freeze)	Last in spring	May 22	May 3 – Jun 4	–	100%
28°F or colder (hard freeze)	First in fall	Oct 5	Sep 22 – Oct 24	Sep 13 (2016) / Oct 29 (2024)	100%
28°F or colder (hard freeze)	Last in spring	May 5	Apr 20 – May 15	–	100%

Based on the station’s daily minimum temperature, 1995–2024. “Freeze” here means a daily low at or below the threshold, which is not the same as visible frost. Your yard can differ by several degrees and days from an airport weather station, so use these as planning odds, not guarantees.

The median stretch between the last spring freeze and the first fall freeze (the freeze-free season) was about 124 days.

Nearby weather stations

Source station: Great Falls Ap (USW00024143), elevation 3,667 ft. Data: NOAA NCEI GHCN-Daily. Computed by First Snow Dates; how we calculate this. Historical averages only; for a forecast see weather.gov.

Planning for winter? Heat pump vs gas furnace, propane and oil: heating cost in Montana (on our sister site PlugVsPump, from EIA prices).