Great Falls climate — normals and trends
Great Falls (United States) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 7.6 °C and it receives 443 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (21.4 °C on average) and the coldest is January (-4.9 °C). Rainfall peaks in June.
Great Falls averages 136 frost days, 32 hot days (≥ 30 °C) and 89 rainy days per year.
Great Falls has warmed by +1.8 °C between 1940 and 2025, or +0.21 °C per decade. This trend is statistically significant.
The number of frost days there went from about 147 to 125 per year over the period.
The hottest day of the period reached 41.8 °C (on 5 August 1961) and the coldest -42.3 °C (on 2 February 1996).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
Great FallsMontana
- coords
- 47.50°, -111.30°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
7.6°C
Average daily high
13.4°C
Average daily low
2.0°C
Annual rainfall
443mm
Sunshine / day
9.8h
Mean relative humidity
56%
Average peak wind
20.4km/h
Seasonal range
26.3°C
Frost days (< 0 °C)
136 d/yr
Hot days (≥ 30 °C)
32 d/yr
Rainy days (≥ 1 mm)
89 d/yr
Annual snowfall
104.6 cm
Average feels-like high
9.5 °C
Average feels-like low
-1.9 °C
Average peak gust
38.6 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
15.5 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.8 °C
since 1940
+0.2 °C per decade · r² = 0.24 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
41.8 °C
5 August 1961
Coldest day
-42.3 °C
2 February 1996
Wettest day
78 mm
3 June 1953
Windiest day
59.4 km/h
10 December 1956
Strongest gust
106.2 km/h
13 January 2021
Hottest feels-like
39.4 °C
5 August 1961
Coldest feels-like
-47.7 °C
2 February 1996
Snowiest day
30.0 cm
28 May 1982
Sunniest day
15.1 h
18 June 2025
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | -2.0 °C | -1.6 °C | 42 mm | +19 mm |
| Feb | -6.3 °C | -8.1 °C | 31 mm | +10 mm |
| Mar | 10.5 °C | +4.2 °C | 25 mm | -5 mm |
| Apr | 14.1 °C | +1.4 °C | 40 mm | -10 mm |
| May | 21.3 °C | +3.1 °C | 53 mm | -17 mm |
| Jun | 24.2 °C | +1.5 °C | 51 mm | -20 mm |
| Jul | 28.1 °C | -0.6 °C | 47 mm | +20 mm |
| Aug | 28.1 °C | +0.4 °C | 18 mm | -14 mm |
| Sep | 25.9 °C | +4.6 °C | 14 mm | -26 mm |
| Oct | 14.4 °C | +0.1 °C | 25 mm | -7 mm |
| Nov | 10.4 °C | +4.5 °C | 21 mm | -4 mm |
| Dec | 5.8 °C | +4.7 °C | 30 mm | +7 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Great Falls?
Great Falls has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 7.6 °C and it receives 443 mm of precipitation per year.
What is the hottest day ever recorded in Great Falls?
The hottest day measured in Great Falls between 1940 and 2025 was 5 August 1961, reaching 41.8 °C.
What is the coldest day in Great Falls?
The coldest day measured in Great Falls between 1940 and 2025 was 2 February 1996, at -42.3 °C.
Does it snow in Great Falls?
Yes. Great Falls gets on average 104.6 cm of snow per year and has around 136 frost days.
Has the climate of Great Falls warmed?
Yes: Great Falls warmed by +1.8 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Great Falls?
The wettest day measured in Great Falls between 1940 and 2025 was 3 June 1953, with 78 mm of rain in 24 hours.
What was the windiest day in Great Falls?
The windiest day measured in Great Falls between 1940 and 2025 was 10 December 1956, with winds reaching 59.4 km/h.
What is the warmest month in Great Falls?
The warmest month in Great Falls is July (21.4 °C on average); the coldest is January (-4.9 °C).
How much does it rain in Great Falls?
Great Falls receives on average 443 mm of precipitation per year, spread over about 89 rainy days.
Is it sunny in Great Falls?
Great Falls gets on average 9.8 hours of sunshine per day, roughly 3,577 hours per year over 1940-2025.
What is the biggest single-day snowfall in Great Falls?
The heaviest 24-hour snowfall measured in Great Falls between 1940 and 2025 was 28 May 1982, with 30.0 cm.
Are there tropical nights in Great Falls?
Yes: Great Falls has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Great Falls?
In Great Falls, between 1940 and 2025, the highest apparent temperature reached 39.4 °C on 5 August 1961, and the lowest was -47.7 °C on 2 February 1996.
Compare Great Falls with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Great Falls