Thurston County (Olympia)
September
Weather in Thurston County, Washington for September 2025
Your guide to Thurston County weather in September - trends and predictions
In general, the average temperature in Thurston County at the beginning of September is 29 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 18.9 °F by the end of September.
Thurston County experiences moderate rainfall in September, with an average of 8 rainy days and a total precipitation of 33.2 mm.
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Temperatures
Rain 🌧️
More
22
Dry days
8
Rainy days
0
Snow days
22°/11°
Temperatures
10 km/h
Avg max wind
76 %
Avg humidity
Thurston County Weather September
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Temperatures trend during September in Thurston County
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September weather in Thurston County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 31° /14° | 0 mm | 7 | |
| Sept. 2 | Overcast | 23° /12° | 0 mm | 5 | |
| Sept. 3 | Overcast | 24° /14° | 0 mm | 5 | |
| Sept. 4 | Overcast | 28° /11° | 0 mm | 6 | |
| Sept. 5 |  Sunny | 33° /13° | 0 mm | 8 | |
| Sept. 6 | Sunny | 33° /14° | 0 mm | 8 | |
| Sept. 7 |  Partly cloudy | 31° /15° | 0 mm | 8 | |
| Sept. 8 | Sunny | 27° /12° | 0 mm | 7 | |
| Sept. 9 | Overcast | 23° /12° | 0 mm | 5 | |
| Sept. 10 | Overcast | 21° /9° | 1.1 mm | 5 | |
| Sept. 11 |  Moderate rain at times | 16° /10° | 11 mm | 4 | |
| Sept. 12 |  Patchy rain possible | 19° /11° | 1.4 mm | 4 | |
| Sept. 13 | Moderate rain at times | 20° /8° | 1.2 mm | 5 | |
| Sept. 14 |  Heavy rain at times | 19° /10° | 2 mm | 4 | |
| Sept. 15 | Patchy rain possible | 19° /9° | 0.8 mm | 4 | |
| Sept. 16 | Overcast | 22° /8° | 0 mm | 5 | |
| Sept. 17 | Overcast | 16° /11° | 0 mm | 4 | |
| Sept. 18 | Patchy rain possible | 18° /12° | 0.1 mm | 4 | |
| Sept. 19 | Patchy rain possible | 17° /12° | 0.1 mm | 4 | |
| Sept. 20 | Overcast | 18° /10° | 0 mm | 4 | |
| Sept. 21 |  Cloudy | 19° /9° | 0 mm | 4 | |
| Sept. 22 | Overcast | 19° /10° | 0 mm | 4 | |
| Sept. 23 | Patchy rain possible | 21° /15° | 0.1 mm | 5 | |
| Sept. 24 | Cloudy | 26° /15° | 0 mm | 6 | |
| Sept. 25 | Moderate or heavy rain shower | 19° /13° | 9.6 mm | 4 | |
| Sept. 26 | Heavy rain at times | 17° /10° | 5.8 mm | 4 | |
| Sept. 27 | Overcast | 19° /12° | 0 mm | 4 | |
| Sept. 28 | Overcast | 17° /9° | 0 mm | 4 | |
| Sept. 29 | Partly cloudy | 17° /8° | 0 mm | 5 | |
| Sept. 30 | Overcast | 17° /9° | 0 mm | 4 | |
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Important Notice
Our weather forecast for Thurston 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 Thurston County forecast closer to your planned date for the most up-to-date weather information.
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Thurston County in September - FAQ
What are the expected maximum and minimum temperatures in Thurston County during September?
Enjoy moderate daytime temperatures of up to 22° and cooler nights around 11°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Thurston County during September?
In September, Thurston County can expect light to moderate rainfall, totaling 33.2 mm across approximately 8 days. Occasional showers are possible, and planning ahead for them could be helpful.
What are the typical wind conditions in Thurston County during September?
The average wind speed in Thurston County during September is 10 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Thurston County
Explore the daily rainfall trends and prepare for Thurston Countys September weather 💧
UV exposure in Thurston County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Thurston County?Get accurate weather forecasts for Thurston County, located at latitude 47.038 and longitude -122.901. Stay updated with localized weather information tailored for Thurston County.
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