Nez Perce County (Lewiston)
September
Weather in Nez Perce County, Idaho for September 2026
Your guide to Nez Perce County weather in September - trends and predictions
Until now, September 2026 in Nez Perce County is cooler than usual, with temperatures averaging 23.7 °F, this is 2.9 °F below the typical seasonal average.
The forecast for the upcoming days in Nez Perce County predicts a temperature of 18.7 °F, which is slightly above the historical average.
In general, the average temperature in Nez Perce County at the beginning of September is 30.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 17.7 °F by the end of September.
With an average of 4 rainy days, Nez Perce County experiences minimal rainfall in September.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
26
Dry days
4
Rainy days
0
Snow days
27°/13°
Temperatures
14 km/h
Avg max wind
45 %
Avg humidity
Nez Perce County Weather September
Move between months or click on a day
Temperatures trend during September in Nez Perce County
See the weather trend as well as the moving average line
September weather in Nez Perce County day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 35° /17° | 0.1 mm | 5 | |
| Sept. 2 | Sunny | 31° /16° | 18.2 mm | 6 | |
| Sept. 3 | Sunny | 29° /16° | 70.6 mm | 6 | |
| Sept. 4 | Sunny | 32° /14° | 10.4 mm | 8 | |
| Sept. 5 | Sunny | 29° /12° | 0 mm | 7 | |
| Sept. 6 |  Cloudy | 29° /12° | 0.4 mm | 5 | |
| Sept. 7 |  Overcast | 27° /14° | 0.9 mm | 4 | |
| Sept. 8 |  Thundery outbreaks possible | 28° /11° | 0 mm | 6 | |
| Sept. 9 | Overcast | 28° /13° | 0 mm | 6 | |
| Sept. 10 | Overcast | 28° /15° | 0 mm | 5 | |
| Sept. 11 | Overcast | 23° /14° | 1.1 mm | 4 | |
| Sept. 12 |  Moderate rain at times | 24° /12° | 2.9 mm | 3 | |
| Sept. 13 |  Partly cloudy | 23° /10° | 6.2 mm | 5 | |
| Sept. 14 | Partly cloudy | 21° /11° | 4.9 mm | 4 | |
| Sept. 15 | Overcast | 20° /10° | 0 mm | 4 | |
| Sept. 16 | Sunny | 25° /10° | 0.3 mm | 6 | |
| Sept. 17 | Moderate or heavy rain shower | 24° /12° | 0.6 mm | 5 | |
| Sept. 18 | Overcast | 26° /12° | 0 mm | 6 | |
| Sept. 19 | Sunny | 28° /13° | 0 mm | 6 | |
| Sept. 20 | Sunny | 26° /12° | 0 mm | 6 | |
| Sept. 21 | Overcast | 23° /11° | 0 mm | 5 | |
| Sept. 22 | Cloudy | 23° /11° | 0 mm | 4 | |
| Sept. 23 | Overcast | 21° /11° | 0 mm | 4.2 | |
| Sept. 24 | Overcast | 25° /13° | 0 mm | 4.5 | |
| Sept. 25 | Sunny | 19° /12° | 1 mm | 3.7 | |
| Sept. 26 | Overcast | 16° /7° | 0 mm | 4.2 | |
| Sept. 27 | Overcast | 13° /8° | 1.5 mm | 3 | |
| Sept. 28 |  Patchy rain possible | 14° /8° | 0.6 mm | 3 | |
| Sept. 29 | Sunny | 16° /7° | 0 mm | 4 | |
| Sept. 30 | Overcast | 21° /11° | 0 mm | 6 | |
| Next | |||||
Important Notice
Our weather forecast for Nez Perce 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 Nez Perce County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Nez Perce County in September - FAQ
What are the expected maximum and minimum temperatures in Nez Perce County during September?
Enjoy moderate daytime temperatures of up to 27° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Nez Perce County during September?
Expect minimal rainfall in Nez Perce County during September, with a total of 14.2 mm over approximately 4 days. This minimal precipitation is unlikely to significantly impact plans.
What are the typical wind conditions in Nez Perce County during September?
The average wind speed in Nez Perce County during September is 14 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Nez Perce County
Explore the daily rainfall trends and prepare for Nez Perce Countys September weather 💧
Typically, Nez Perce County has 4 rainy days in September with a total of 14.2 mm of rainfall.
UV exposure in Nez Perce County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Top locations in Nez Perce County
Select a location for an accurate weather forecast
More Locations Quick links
More Nez Perce County weather pages
You are here
Where is Nez Perce County?Get accurate weather forecasts for Nez Perce County, located at latitude 46.417 and longitude -117.018. Stay updated with localized weather information tailored for Nez Perce County.
Found a mistake?
We appreciate your attention to details. Tell us here.