Great Falls, MT Weather Forecast | 5 Day
Updated: Sat Sep 12th 2026 11:45 PM MDT
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Overcast
Sat 9-12-26
- HI: 58°F
- LO: 41°F
- Rainfall: 21%
- Snowfall: 0%
- Wind
11.9 mph - Humidity
78% avg. - UV Index
3.8 - Air Quality
- Sunrise
06:58 AM - Sunset
07:44 PM - Moonrise
08:49 AM - Moonset
08:03 PM - Moon Phase
New Moon
Sunny
Weather Tomorrow, Sun 9-13-26
Sunny with a high of 68°F and a low of 44°F. Rainfall expected to have a 57% chance with an estimated 0.05in. Wind will be moderate, blowing around 16mph on average and gusts of 24.4mph at 6 PM. The humidity will be on the higher side, averaging about 62%, the maximum being 85% at 4 AM and 36% being its lowest at 3 PM. Barometric pressure is its highest of 30.06inHg at 12 AM, a lowest point of 29.7inHg at 4 PM with an avg 29.87inHg.
- HI: 68°F
- LO: 44°F
- Rainfall: 57% | est. 0.05in
- Snowfall: 0%
- Wind
15.4 mph - Humidity
62% avg. - UV Index
5.2 - Air QualityGood
- Sunrise
06:59 AM - Sunset
07:42 PM - Moonrise
10:11 AM - Moonset
08:23 PM - Moon Phase
Waxing Crescent
Overcast
Mon 9-14-26
Overcast with a high of 59°F and a low of 48°F. Rainfall expected to have a 57% chance with an estimated 0.04in. Winds will be strong at speeds peaking at 21mph and gusts of 34.5mph at 7 AM. Humidity levels should be comfortable, sitting around 57% on average, the maximum being 72% at 3 AM and 44% being its lowest at 1 PM. Barometric pressure is its highest of 30.11inHg at 11 PM, a lowest point of 29.76inHg at 12 AM with an avg 29.89inHg.
- HI: 59°F
- LO: 48°F
- Rainfall: 57% | est. 0.04in
- Snowfall: 0%
- Wind
20.1 mph - Humidity
57% avg. - UV Index
1.7 - Air QualityGood
- Sunrise
07:01 AM - Sunset
07:40 PM - Moonrise
11:31 AM - Moonset
08:46 PM - Moon Phase
Waxing Crescent
Overcast
Tue 9-15-26
Overcast with a high of 66°F and a low of 46°F. There's a very small chance of rainfall, only about 10%. Winds will be light at 10mph and gusts of 17.4mph at 4 PM. Humidity levels should be comfortable, sitting around 55% on average, the maximum being 80% at 7 AM and 34% being its lowest at 5 PM. Barometric pressure is its highest of 30.13inHg at 6 AM, a lowest point of 29.93inHg at 6 PM with an avg 30.04inHg.
- HI: 66°F
- LO: 46°F
- Rainfall: 10%
- Snowfall: 0%
- Wind
9.6 mph - Humidity
55% avg. - UV Index
4.1 - Air QualityGood
- Sunrise
07:02 AM - Sunset
07:37 PM - Moonrise
12:50 PM - Moonset
09:15 PM - Moon Phase
Waxing Crescent
Sunny
Wed 9-16-26
Sunny with a high of 72°F and a low of 48°F. There's a very small chance of rainfall, only about 3%. Winds will be light at 8mph and gusts of 16.3mph at 7 AM. Humidity levels should be comfortable, sitting around 51% on average, the maximum being 70% at 11 AM and 28% being its lowest at 5 PM. Barometric pressure is its highest of 30.18inHg at 11 AM, a lowest point of 29.99inHg at 12 AM with an avg 30.07inHg.
- HI: 72°F
- LO: 48°F
- Rainfall: 3%
- Snowfall: 0%
- Wind
7.8 mph - Humidity
51% avg. - UV Index
4.3 - Air QualityGood
- Sunrise
07:03 AM - Sunset
07:35 PM - Moonrise
02:03 PM - Moonset
09:52 PM - Moon Phase
First Quarter
Sunny
Thu 9-17-26
Sunny with a high of 74°F and a low of 50°F. There's a very small chance of rainfall, only about 1%. Winds will be light at 6mph and gusts of 17.2mph at 6 PM. Humidity levels should be comfortable, sitting around 38% on average, the maximum being 53% at 7 AM and 22% being its lowest at 3 PM. Barometric pressure is its highest of 30.19inHg at 8 AM, a lowest point of 30.07inHg at 6 PM with an avg 30.13inHg.
- HI: 74°F
- LO: 50°F
- Rainfall: 1%
- Snowfall: 0%
- Wind
6 mph - Humidity
38% avg. - UV Index
6 - Air QualityGood
- Sunrise
07:05 AM - Sunset
07:33 PM - Moonrise
03:08 PM - Moonset
10:38 PM - Moon Phase
First Quarter
This 5-Day weather forecast is relevant for ZIP codes 59401, 59403, 59404, 59405, and 59406, accurately covering areas of Great Falls, MT.
Currently
 |
50°F |
30.06 inHg.
Barometer 79%
Humidity NE 17.6 mph Wind |
| Partly Cloudy | ||
National Outlook
Rain and Thunder in Central and Eastern U.S., Cool in Northwest 09-12 to 09-14
Sat Sep 12th 2026, 5:56am PDT
Read
Watch Out: Heat and Storms Ahead - 09-14 to 09-18
Extended Forecast
Sat Sep 12th 2026, 6:03am PDT
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Sat Sep 12th 2026, 6:03am PDT
5 Day Forecast Nearby
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