Annual mean 14°C · wettest around May · prevailing wind W
Warmest
30.7 °C
Coldest
4.1 °C
Wettest
59%
Windiest
4.7 m/s
Prevailing
W
3.6 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Great Falls over the whole year is 14°C. July is the hottest month, with highs of about 30°C; January is the coldest, with lows of about -1°C. Great Falls has no sharply defined rainy season: the chance of rain on a given day runs from 49% in October, the driest month, to 56% in May, the wettest. Winds in Great Falls are highest in March, averaging 3.4 m/s (12 km/h), and lightest in August, at 1.9 m/s (7 km/h). The prevailing wind is from the W. The clearest skies in Great Falls come in November, when the sky is typically 42% covered; May is the cloudiest month, at 58%.
Month by month Great Falls climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
4°C
-1°C
-1°C
53%
54%
3.0 m/s
3
0
13
February
7°C
2°C
2°C
56%
52%
2.9 m/s
5
0
25
March
11°C
4°C
6°C
54%
49%
3.4 m/s
16
0
44
April
17°C
9°C
13°C
52%
51%
3.2 m/s
38
7
61
May
21°C
14°C
20°C
56%
58%
2.4 m/s
59
23
57
June
27°C
19°C
27°C
50%
46%
2.4 m/s
50
49
25
July
30°C
22°C
32°C
52%
44%
2.0 m/s
17
52
4
August
28°C
20°C
30°C
54%
47%
1.9 m/s
34
56
10
September
25°C
17°C
25°C
54%
49%
2.0 m/s
63
40
37
October
19°C
11°C
17°C
49%
47%
2.2 m/s
56
14
68
November
12°C
5°C
8°C
53%
42%
2.5 m/s
17
1
50
December
7°C
2°C
2°C
56%
54%
2.5 m/s
2
0
25
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Great Falls weather by season
Year round, Great Falls has days of about 4°C at their warmest in January, its coolest month, and 30°C in July, its warmest; the coolest hours of the day run from -1°C to 22°C through the year, and the average temperature over the year is 14°C around the clock. Rain is most likely around May and least likely around October. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Great Falls weather in winterDecember to February
High 6°CLow 1°CRain 55%
Winter in Great Falls has typical daily highs of about 6°C and lows of about 1°C, with a 55% chance of rain on a given day.
Great Falls weather in springMarch to May
High 17°CLow 9°CRain 54%
Spring in Great Falls has typical daily highs of about 17°C and lows of about 9°C, with a 54% chance of rain on a given day.
Great Falls weather in summerJune to August
High 28°CLow 21°CRain 52%
Summer in Great Falls has typical daily highs of about 28°C and lows of about 21°C, with a 52% chance of rain on a given day.
Great Falls weather in autumnSeptember to November
High 19°CLow 11°CRain 52%
Autumn in Great Falls has typical daily highs of about 19°C and lows of about 11°C, with a 52% chance of rain on a given day.
When is the rainy season in Great Falls?
Great Falls has no sharply defined rainy season: the chance of rain on a given day runs from 49% in October, the driest month, to 56% in May, the wettest.
What time of year is Great Falls windiest?
Winds in Great Falls are highest in March, averaging 3.4 m/s (12 km/h), and lightest in August, at 1.9 m/s (7 km/h). The prevailing wind is from the W.
What is the average temperature in Great Falls year round?
The average temperature in Great Falls over the whole year is 14°C. July is the hottest month, with highs of about 30°C; January is the coldest, with lows of about -1°C.