Missoula County (Missoula)
September
Weather in Missoula County, Montana for September 2026
Your guide to Missoula County weather in September - trends and predictions
Until now, September 2026 in Missoula County is cooler than usual, with temperatures averaging 21.4 °F, this is 2.4 °F below the typical seasonal average.
The forecast for the coming days of September 2026 predicts a temperature of 22.8 °F , which is warmer than usual.
In general, the average temperature in Missoula County at the beginning of September is 27.1 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 21.4 °F by the end of September.
Missoula County experiences moderate rainfall in September, with an average of 9 rainy days and a total precipitation of 79.7 mm.
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Temperatures
Rain 🌧️
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21
Dry days
9
Rainy days
0
Snow days
24°/10°
Temperatures
11 km/h
Avg max wind
48 %
Avg humidity
Missoula County Weather September
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Temperatures trend during September in Missoula County
See the weather trend as well as the moving average line
September weather in Missoula County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 32° /12° | 0.2 mm | 7 | |
| Sept. 2 | Overcast | 30° /12° | 5.3 mm | 5 | |
| Sept. 3 |  Patchy rain possible | 25° /12° | 5.6 mm | 5 | |
| Sept. 4 |  Sunny | 25° /11° | 11.6 mm | 5 | |
| Sept. 5 | Sunny | 26° /10° | 4 mm | 5 | |
| Sept. 6 | Sunny | 27° /9° | 21.7 mm | 5 | |
| Sept. 7 | Sunny | 25° /11° | 46.2 mm | 5 | |
| Sept. 8 | Sunny | 26° /9° | 0 mm | 7 | |
| Sept. 9 | Sunny | 26° /10° | 0.6 mm | 6 | |
| Sept. 10 | Patchy rain possible | 27° /11° | 0 mm | 6 | |
| Sept. 11 |  Moderate or heavy rain shower | 22° /10° | 6.6 mm | 4 | |
| Sept. 12 | Overcast | 18° /9° | 12.2 mm | 3 | |
| Sept. 13 | Patchy rain possible | 19° /8° | 1.2 mm | 4 | |
| Sept. 14 | Overcast | 20° /7° | 3.2 mm | 4 | |
| Sept. 15 | Overcast | 17° /7° | 1.5 mm | 3 | |
| Sept. 16 | Sunny | 23° /7° | 1.2 mm | 5 | |
| Sept. 17 | Moderate or heavy rain shower | 23° /9° | 4.6 mm | 5 | |
| Sept. 18 | Moderate or heavy rain shower | 21° /10° | 20.9 mm | 4 | |
| Sept. 19 |  Partly cloudy | 22° /9° | 0.4 mm | 5 | |
| Sept. 20 | Sunny | 23° /9° | 0 mm | 6 | |
| Sept. 21 |  Cloudy | 21° /8° | 0 mm | 5 | |
| Sept. 22 | Overcast | 21° /7° | 0 mm | 4 | |
| Sept. 23 | Partly cloudy | 24° /8° | 0 mm | 5 | |
| Sept. 24 | Sunny | 26° /8° | 0 mm | 6 | |
| Sept. 25 | Partly cloudy | 27° /10° | 0.1 mm | 5 | |
| Sept. 26 | Patchy rain possible | 20° /12° | 2.5 mm | 5 | |
| Sept. 27 | Overcast | 16° /2° | 0 mm | 3.4 | |
| Sept. 28 | Sunny | 20° /5° | 0 mm | 4.2 | |
| Sept. 29 | Sunny | 20° /4° | 0 mm | 4.4 | |
| Sept. 30 | Overcast | 21° /7° | 0 mm | 4.5 | |
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Important Notice
Our weather forecast for Missoula County in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Missoula County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Missoula County in September - FAQ
What are the expected maximum and minimum temperatures in Missoula County during September?
Enjoy moderate daytime temperatures of up to 24° and cooler nights around 10°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Missoula County during September?
Moderate rainfall is anticipated in Missoula County during September, with a total of 79.7 mm spread over approximately 9 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Missoula County during September?
The average wind speed in Missoula County during September is 11 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Missoula County
Explore the daily rainfall trends and prepare for Missoula Countys September weather 💧
Typically, Missoula County has 9 rainy days in September with a total of 79.7 mm of rainfall.
UV exposure in Missoula County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Missoula County?Get accurate weather forecasts for Missoula County, located at latitude 46.872 and longitude -113.994. Stay updated with localized weather information tailored for Missoula County.
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