Kittitas County (Snoqualmie Pass)
September
Weather in Kittitas County, Washington for September 2026
Your guide to Kittitas County weather in September - trends and predictions
In general, the average temperature in Kittitas County at the beginning of September is 25.3 °C. As the month progressed, temperatures tended to significantly cool down, reaching an average of 16 °C by the end of September.
Kittitas County experiences moderate rainfall in September, with an average of 6 rainy days and a total precipitation of 63.2 mm.
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Temperatures
Rain 🌧️
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24
Dry days
6
Rainy days
0
Snow days
19°/10°
Temperatures
11 km/h
Avg max wind
70 %
Avg humidity
Kittitas County Weather September
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Temperatures trend during September in Kittitas County
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September weather in Kittitas County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Mist | 21° /12° | 0 mm | 6 | |
| Sept. 2 |  Sunny | 29° /14° | 0 mm | 7 | |
| Sept. 3 |  Thundery outbreaks possible | 31° /20° | 0 mm | 7 | |
| Sept. 4 |  Cloudy | 30° /19° | 0 mm | 7 | |
| Sept. 5 | Sunny | 26° /17° | 0 mm | 7 | |
| Sept. 6 | Thundery outbreaks possible | 25° /18° | 0 mm | 6 | |
| Sept. 7 |  Moderate rain | 15° /11° | 14 mm | 1 | |
| Sept. 8 | Mist | 15° /9° | 0 mm | 2 | |
| Sept. 9 |  Moderate rain at times | 12° /10° | 19.6 mm | 1 | |
| Sept. 10 | Mist | 17° /11° | 0 mm | 3 | |
| Sept. 11 | Mist | 11° /9° | 0 mm | 1 | |
| Sept. 12 | Mist | 11° /9° | 0 mm | 2 | |
| Sept. 13 |  Partly cloudy | 23° /10° | 0 mm | 6 | |
| Sept. 14 |  Light rain | 12° /7° | 7.7 mm | 1 | |
| Sept. 15 | Mist | 19° /6° | 0 mm | 4 | |
| Sept. 16 | Sunny | 21° /12° | 0 mm | 5 | |
| Sept. 17 | Sunny | 23° /14° | 0 mm | 5 | |
| Sept. 18 | Mist | 18° /9° | 0 mm | 4 | |
| Sept. 19 | Sunny | 23° /11° | 0 mm | 5 | |
| Sept. 20 | Cloudy | 17° /7° | 0 mm | 5 | |
| Sept. 21 |  Heavy rain at times | 10° /6° | 7.8 mm | 2 | |
| Sept. 22 | Mist | 18° /4° | 0 mm | 4 | |
| Sept. 23 | Sunny | 21° /10° | 0 mm | 4 | |
| Sept. 24 | Sunny | 23° /13° | 0 mm | 4 | |
| Sept. 25 | Mist | 12° /7° | 0 mm | 3 | |
| Sept. 26 |  Overcast | 14° /3° | 0 mm | 4 | |
| Sept. 27 | Overcast | 20° /9° | 0 mm | 4 | |
| Sept. 28 | Overcast | 19° /10° | 0 mm | 4 | |
| Sept. 29 | Moderate or heavy rain shower | 12° /9° | 6.4 mm | 1 | |
| Sept. 30 | Heavy rain at times | 12° /6° | 7.7 mm | 3 | |
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Important Notice
Our weather forecast for Kittitas 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 Kittitas County forecast closer to your planned date for the most up-to-date weather information.
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Kittitas County in September - FAQ
What are the expected maximum and minimum temperatures in Kittitas County during September?
Enjoy moderate daytime temperatures of up to 19° and cooler nights around 10°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Kittitas County during September?
Moderate rainfall is anticipated in Kittitas County during September, with a total of 63.2 mm spread over approximately 6 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Kittitas County during September?
The average wind speed in Kittitas County during September is 11 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Kittitas County
Explore the daily rainfall trends and prepare for Kittitas Countys September weather 💧
Typically, Kittitas County has 6 rainy days in September with a total of 63.2 mm of rainfall.
UV exposure in Kittitas County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Kittitas County?Get accurate weather forecasts for Kittitas County, located at latitude 47.392 and longitude -121.4. Stay updated with localized weather information tailored for Kittitas County.
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