Great Falls weather by month

Check out Great Falls weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature in Great Falls (°C)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
-2°C maximum daytime temperature in January in Great Falls-2
3°C maximum daytime temperature in February in Great Falls3
6°C maximum daytime temperature in March in Great Falls6
13°C maximum daytime temperature in April in Great Falls13
18°C maximum daytime temperature in May in Great Falls18
23°C maximum daytime temperature in June in Great Falls23
28°C maximum daytime temperature in July in Great Falls28
28°C maximum daytime temperature in August in Great Falls28
21°C maximum daytime temperature in September in Great Falls21
15°C maximum daytime temperature in October in Great Falls15
7°C maximum daytime temperature in November in Great Falls7
0°C maximum daytime temperature in December in Great Falls0
Min temperature (night-time)
-12°C minimum night-time temperature in January in Great Falls-12
-8°C minimum night-time temperature in February in Great Falls-8
-6°C minimum night-time temperature in March in Great Falls-6
0°C minimum night-time temperature in April in Great Falls0
5°C minimum night-time temperature in May in Great Falls5
9°C minimum night-time temperature in June in Great Falls9
12°C minimum night-time temperature in July in Great Falls12
11°C minimum night-time temperature in August in Great Falls11
6°C minimum night-time temperature in September in Great Falls6
2°C minimum night-time temperature in October in Great Falls2
-5°C minimum night-time temperature in November in Great Falls-5
-10°C minimum night-time temperature in December in Great Falls-10
Heat & Humidity
No heat & humidity in January in Great Falls0
No heat & humidity in February in Great Falls0
No heat & humidity in March in Great Falls0
No heat & humidity in April in Great Falls0
No heat & humidity in May in Great Falls0
No heat & humidity in June in Great Falls0
Low heat & humidity in July in Great FallsL
Low heat & humidity in August in Great FallsL
No heat & humidity in September in Great Falls0
No heat & humidity in October in Great Falls0
No heat & humidity in November in Great Falls0
No heat & humidity in December in Great Falls0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & Daylight in Great Falls

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily hours of sunshine
Daily hours of daylight
9 hours of daylight per day in January in Great Falls9
10 hours of daylight per day in February in Great Falls10
12 hours of daylight per day in March in Great Falls12
14 hours of daylight per day in April in Great Falls14
15 hours of daylight per day in May in Great Falls15
16 hours of daylight per day in June in Great Falls16
15 hours of daylight per day in July in Great Falls15
14 hours of daylight per day in August in Great Falls14
13 hours of daylight per day in September in Great Falls13
11 hours of daylight per day in October in Great Falls11
9 hours of daylight per day in November in Great Falls9
9 hours of daylight per day in December in Great Falls9
UV Index (Maximum)
UV (maximum) index 1 (Low) in January in Great Falls1
UV (maximum) index 2 (Low) in February in Great Falls2
UV (maximum) index 3 (Moderate) in March in Great Falls3
UV (maximum) index 5 (Moderate) in April in Great Falls5
UV (maximum) index 6 (High) in May in Great Falls6
UV (maximum) index 8 (Very High) in June in Great Falls8
UV (maximum) index 8 (Very High) in July in Great Falls8
UV (maximum) index 7 (High) in August in Great Falls7
UV (maximum) index 5 (Moderate) in September in Great Falls5
UV (maximum) index 3 (Moderate) in October in Great Falls3
UV (maximum) index 1 (Low) in November in Great Falls1
UV (maximum) index 1 (Low) in December in Great Falls1

Rainfall in Great Falls

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
9 days with some rainfall in January in Great Falls9
7 days with some rainfall in February in Great Falls7
9 days with some rainfall in March in Great Falls9
9 days with some rainfall in April in Great Falls9
12 days with some rainfall in May in Great Falls12
11 days with some rainfall in June in Great Falls11
7 days with some rainfall in July in Great Falls7
8 days with some rainfall in August in Great Falls8
7 days with some rainfall in September in Great Falls7
5 days with some rainfall in October in Great Falls5
6 days with some rainfall in November in Great Falls6
9 days with some rainfall in December in Great Falls9
Average monthly rainfall (mm)
20 mm monthly rainfall in January in Great Falls20
14 mm monthly rainfall in February in Great Falls14
23 mm monthly rainfall in March in Great Falls23
31 mm monthly rainfall in April in Great Falls31
63 mm monthly rainfall in May in Great Falls63
71 mm monthly rainfall in June in Great Falls71
34 mm monthly rainfall in July in Great Falls34
36 mm monthly rainfall in August in Great Falls36
26 mm monthly rainfall in September in Great Falls26
19 mm monthly rainfall in October in Great Falls19
16 mm monthly rainfall in November in Great Falls16
18 mm monthly rainfall in December in Great Falls18

More about Great Falls

Great Falls by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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The climate guide for Montana (Great Falls) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Great Falls?

Great Falls has a cold semi arid climate with warm summers.

Metric (°C / mm)  |  Imperial (°F / inches)

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More about the USA

Compare Great Falls with the USA

Below the Great Falls chart shows average maximum daytime temperature for Great Falls, Montana, USA and the USA (Washington).

Maximum daytime temperature (°C)

Great Falls, Montana, USA
USA (Washington)
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Metric (°C / mm)  |  Imperial (°F / inches)

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