Idaho (Coeur d'Alene)
September
Weather in Idaho for September 2026
Your guide to Idaho weather in September - trends and predictions
Until now, September 2026 in Idaho is cooler than usual, with temperatures averaging 21 °F, this is 3.8 °F below the typical seasonal average.
The forecast for the upcoming days in Idaho predicts a temperature of 17.3 °F, which is slightly above the historical average.
In general, the average temperature in Idaho at the beginning of September is 28.7 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 16.1 °F by the end of September.
Idaho experiences moderate rainfall in September, with an average of 10 rainy days and a total precipitation of 32.9 mm.
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Temperatures
Rain 🌧️
More
20
Dry days
10
Rainy days
0
Snow days
25°/13°
Temperatures
11 km/h
Avg max wind
47 %
Avg humidity
Idaho Weather September
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What’s the Weather Like in Idaho This September?
Discover the average temperatures and weather trends across Idaho’s cities this September.
Temperatures trend during September in Idaho
See the weather trend as well as the moving average line
September weather in Idaho day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Partly cloudy | 34° /15° | 0 mm | 6 | |
| Sept. 2 | Partly cloudy | 29° /14° | 12.9 mm | 6 | |
| Sept. 3 |  Cloudy | 27° /15° | 14.3 mm | 5 | |
| Sept. 4 |  Sunny | 26° /14° | 20.8 mm | 5 | |
| Sept. 5 | Sunny | 29° /11° | 0 mm | 7 | |
| Sept. 6 | Sunny | 30° /12° | 0.5 mm | 6 | |
| Sept. 7 |  Overcast | 26° /15° | 15.5 mm | 5 | |
| Sept. 8 | Partly cloudy | 28° /12° | 3.5 mm | 6 | |
| Sept. 9 | Partly cloudy | 26° /13° | 0.9 mm | 6 | |
| Sept. 10 | Partly cloudy | 26° /13° | 1.4 mm | 5 | |
| Sept. 11 |  Moderate rain at times | 20° /12° | 4 mm | 4 | |
| Sept. 12 |  Heavy rain at times | 21° /11° | 1.7 mm | 3 | |
| Sept. 13 | Cloudy | 21° /10° | 3 mm | 4 | |
| Sept. 14 |  Patchy rain possible | 18° /9° | 3.7 mm | 4 | |
| Sept. 15 | Overcast | 19° /9° | 0.9 mm | 4 | |
| Sept. 16 | Sunny | 24° /9° | 0 mm | 6 | |
| Sept. 17 | Heavy rain at times | 22° /12° | 2.6 mm | 5 | |
| Sept. 18 | Overcast | 24° /12° | 0 mm | 6 | |
| Sept. 19 | Cloudy | 25° /12° | 0 mm | 6 | |
| Sept. 20 | Sunny | 24° /12° | 0 mm | 5 | |
| Sept. 21 | Overcast | 22° /10° | 0.5 mm | 5 | |
| Sept. 22 | Overcast | 21° /10° | 0.7 mm | 4 | |
| Sept. 23 | Overcast | 20° /10° | 0 mm | 3.9 | |
| Sept. 24 | Overcast | 24° /11° | 0 mm | 3.9 | |
| Sept. 25 | Overcast | 18° /7° | 3.6 mm | 3.3 | |
| Sept. 26 | Sunny | 15° /2° | 0 mm | 3.8 | |
| Sept. 27 | Overcast | 11° /6° | 1.6 mm | 3 | |
| Sept. 28 | Sunny | 13° /5° | 0.3 mm | 4 | |
| Sept. 29 | Overcast | 14° /6° | 0 mm | 4 | |
| Sept. 30 | Overcast | 18° /10° | 0 mm | 4 | |
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Important Notice
Our weather forecast for Idaho 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 Idaho forecast closer to your planned date for the most up-to-date weather information.
Change Month
Idaho in September - FAQ
What are the expected maximum and minimum temperatures in Idaho during September?
Enjoy moderate daytime temperatures of up to 25° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Idaho during September?
In September, Idaho can expect light to moderate rainfall, totaling 32.9 mm across approximately 10 days. Occasional showers are possible, and planning ahead for them could be helpful.
What are the typical wind conditions in Idaho during September?
The average wind speed in Idaho during September is 11 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Idaho
Explore the daily rainfall trends and prepare for Idahos September weather 💧
Typically, Idaho has 10 rainy days in September with a total of 32.9 mm of rainfall.
UV exposure in Idaho during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Counties in Idaho
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Top locations in Idaho
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Where is Idaho?Get accurate weather forecasts for Idaho, located at latitude 47.678 and longitude -116.78. Stay updated with localized weather information tailored for Idaho.
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