Missoula County (Missoula)
September
Weather in Missoula County, Montana for September 2025
Your guide to Missoula County weather in September - trends and predictions
In general, the average temperature in Missoula County at the beginning of September is 29.9 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 22.1 °F by the end of September.
Missoula County experiences moderate rainfall in September, with an average of 7 rainy days and a total precipitation of 134.1 mm.
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Temperatures
Rain 🌧️
More
23
Dry days
7
Rainy days
0
Snow days
23°/9°
Temperatures
12 km/h
Avg max wind
50 %
Avg humidity
Missoula County Weather September
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Temperatures trend during September in Missoula County
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September weather in Missoula County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 32° /9° | 0 mm | 7 | |
| Sept. 2 | Overcast | 33° /11° | 0 mm | 7 | |
| Sept. 3 |  Patchy rain possible | 23° /12° | 0.5 mm | 5 | |
| Sept. 4 |  Sunny | 27° /9° | 0 mm | 7 | |
| Sept. 5 | Sunny | 30° /9° | 0 mm | 8 | |
| Sept. 6 | Sunny | 32° /10° | 0 mm | 8 | |
| Sept. 7 | Sunny | 32° /10° | 0 mm | 8 | |
| Sept. 8 |  Partly cloudy | 32° /10° | 0 mm | 8 | |
| Sept. 9 | Sunny | 29° /11° | 0 mm | 7 | |
| Sept. 10 | Patchy rain possible | 28° /10° | 0.1 mm | 6 | |
| Sept. 11 |  Moderate or heavy rain shower | 21° /10° | 13 mm | 5 | |
| Sept. 12 | Moderate or heavy rain shower | 11° /9° | 33.7 mm | 3 | |
| Sept. 13 | Patchy rain possible | 17° /8° | 1.4 mm | 4 | |
| Sept. 14 | Overcast | 22° /5° | 0 mm | 5 | |
| Sept. 15 | Patchy rain possible | 19° /7° | 0.2 mm | 4 | |
| Sept. 16 |  Cloudy | 23° /7° | 3.6 mm | 5 | |
| Sept. 17 | Moderate or heavy rain shower | 18° /11° | 13.5 mm | 4 | |
| Sept. 18 | Moderate or heavy rain shower | 15° /10° | 62.6 mm | 4 | |
| Sept. 19 | Partly cloudy | 20° /7° | 0 mm | 6 | |
| Sept. 20 | Partly cloudy | 18° /10° | 0 mm | 5 | |
| Sept. 21 | Cloudy | 17° /5° | 0 mm | 4 | |
| Sept. 22 | Overcast | 20° /6° | 0 mm | 5 | |
| Sept. 23 | Partly cloudy | 20° /10° | 0 mm | 6 | |
| Sept. 24 | Sunny | 25° /9° | 0 mm | 7 | |
| Sept. 25 | Partly cloudy | 28° /13° | 0 mm | 7 | |
| Sept. 26 | Patchy rain possible | 21° /12° | 5.1 mm | 5 | |
| Sept. 27 | Sunny | 24° /8° | 0 mm | 6 | |
| Sept. 28 | Sunny | 28° /8° | 0 mm | 7 | |
| Sept. 29 | Patchy rain possible | 18° /8° | 0.4 mm | 4 | |
| Sept. 30 | Cloudy | 11° /4° | 0 mm | 3 | |
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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.
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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 23° and cooler nights around 9°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Missoula County during September?
Significant rainfall exceeding 134.1 mm is expected in Missoula County during September, occurring over more than 7 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Missoula County during September?
The average wind speed in Missoula County during September is 12 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 💧
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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