ClimateAverages

Great Falls Climate

Montana, United States of America · population 59,638 · 293 weather stations within 200 km · records 1837 to 2025

Average annual daytime high
13.8°C
Warmest month · July
28.4°C
Typical daytime high
Coldest month · January
-13.1°C
Typical overnight low

Great Falls has an average annual daytime high of 13.8°C, based on the 1951 to 1980 baseline. Its warmest month is July, when highs typically reach 28.4°C, and its coldest is January, with overnight lows near -13.1°C.

Month by month averages

MonthAvg highAvg low
January-1.5°C-13.1°CColdest
February3.2°C-9.2°C
March6.3°C-6.9°C
April12.9°C-1.6°C
May18.6°C3.8°C
June22.9°C7.8°C
July28.4°C10.5°CWarmest
August27.8°C10.0°C
September21.8°C5.3°C
October15.6°C0.7°C
November6.8°C-5.3°C
December2.1°C-9.1°C

Temperature range across the year

-15°-4°8°19°30°JanFebMarAprMayJunJulAugSepOctNovDec
Daytime high Overnight low
Hottest year on record
1991
+2.5°C vs. 1951–1980
Coldest year on record
1861
-3.8°C vs. 1951–1980

These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.

Is Great Falls getting hotter?

Since 1900, Great Falls's average temperature has risen by +1.6°C. Compared to the earliest station records that begin in 1837, warming totals +2.2°C.

6.0°6.5°7.1°7.6°8.1°1951–1980 baseline190019251950197520002025

20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.

Best time to visit
May to October

Daytime highs sit within a comfortable 15°C to 26°C range.

FAQ

What is the average temperature in Great Falls?

Great Falls's average annual daytime high is 13.8°C, based on the 1951 to 1980 baseline period. The warmest month is July, with highs averaging 28.4°C, and the coldest is January, with lows averaging -13.1°C.

What is the warmest month in Great Falls?

July is the warmest month in Great Falls, with typical daytime highs of 28.4°C.

What is the hottest year on record for Great Falls?

1991 is the hottest year on record for Great Falls, running +2.5°C above the 1951 to 1980 baseline.

Is Great Falls getting hotter?

Yes. Since 1900, Great Falls has warmed by roughly +1.6°C.

When is the best time to visit Great Falls?

May to October typically offers the most comfortable daytime highs, in the 15°C to 26°C range.

Nearby cities

Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.