Clatsop County (Astoria)
September
Weather in Clatsop County for September 2025
Your guide to Clatsop County weather in September - trends and predictions
In general, the average temperature in Clatsop County at the beginning of September is 20.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 14.9 °F by the end of September.
Clatsop County experiences moderate rainfall in September, with an average of 10 rainy days and a total precipitation of 74.5 mm.
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Temperatures
Rain 🌧️
More
20
Dry days
10
Rainy days
0
Snow days
17°/12°
Temperatures
14 km/h
Avg max wind
87 %
Avg humidity
Clatsop County in September average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  18° | 2  17° | 3 18° | 4  24° | 5 25° | 6 21° | 7  19° |
| 8 18° | 9 17° | 10  16° | 11 16° | 12 16° | 13 16° | 14 17° |
| 15 16° | 16  17° | 17  15° | 18 14° | 19 13° | 20 13° | 21 17° |
| 22 14° | 23 16° | 24 18° | 25  14° | 26 14° | 27 14° | 28 13° |
| 29 14° | 30 17° |
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Temperatures trend during September in Clatsop County
See the weather trend as well as the moving average line
September weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 | Cloudy | 18° /13° | 0 mm | 4 | |
| Sept. 2 | Patchy rain possible | 17° /14° | 0.5 mm | 4 | |
| Sept. 3 | Patchy rain possible | 18° /11° | 0.5 mm | 4 | |
| Sept. 4 | Sunny | 24° /11° | 0 mm | 6 | |
| Sept. 5 | Sunny | 25° /16° | 0 mm | 7 | |
| Sept. 6 | Sunny | 21° /14° | 0 mm | 6 | |
| Sept. 7 | Mist | 19° /14° | 0.2 mm | 4 | |
| Sept. 8 | Patchy rain possible | 18° /12° | 0.1 mm | 4 | |
| Sept. 9 | Patchy rain possible | 17° /11° | 0.2 mm | 4 | |
| Sept. 10 | Overcast | 16° /10° | 0.5 mm | 4 | |
| Sept. 11 | Light rain shower | 16° /11° | 17.4 mm | 4 | |
| Sept. 12 | Light rain shower | 16° /11° | 0.9 mm | 4 | |
| Sept. 13 | Patchy rain possible | 16° /11° | 0 mm | 4 | |
| Sept. 14 | Patchy rain possible | 17° /12° | 0.9 mm | 4 | |
| Sept. 15 | Cloudy | 16° /10° | 0 mm | 4 | |
| Sept. 16 | Partly cloudy | 17° /10° | 0 mm | 5 | |
| Sept. 17 | Moderate or heavy rain shower | 15° /13° | 32.8 mm | 4 | |
| Sept. 18 | Fog | 14° /13° | 0 mm | 3 | |
| Sept. 19 | Fog | 13° /12° | 0 mm | 3 | |
| Sept. 20 | Overcast | 13° /12° | 0 mm | 3 | |
| Sept. 21 | Mist | 17° /10° | 0 mm | 4 | |
| Sept. 22 | Fog | 14° /11° | 0 mm | 3 | |
| Sept. 23 | Fog | 16° /14° | 0 mm | 4 | |
| Sept. 24 | Mist | 18° /13° | 0 mm | 4 | |
| Sept. 25 | Heavy rain at times | 14° /12° | 5.2 mm | 3 | |
| Sept. 26 | Heavy rain at times | 14° /12° | 8.4 mm | 3 | |
| Sept. 27 | Fog | 14° /12° | 6.9 mm | 3 | |
| Sept. 28 | Overcast | 13° /11° | 0 mm | 3 | |
| Sept. 29 | Cloudy | 14° /11° | 0 mm | 3 | |
| Sept. 30 | Partly cloudy | 17° /10° | 0 mm | 5 | |
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Important Notice
Our weather forecast for Clatsop 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 Clatsop County forecast closer to your planned date for the most up-to-date weather information.
Clatsop County in September - FAQ
What are the expected maximum and minimum temperatures in Clatsop County during September?
Enjoy moderate daytime temperatures of up to 17° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Clatsop County during September?
Moderate rainfall is anticipated in Clatsop County during September, with a total of 74.5 mm spread over approximately 10 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Clatsop County during September?
The average wind speed in Clatsop County during September is 14 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Clatsop County
Explore the daily rainfall trends and prepare for Clatsop Countys September weather 💧
UV exposure in Clatsop County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Clatsop County?Get accurate weather forecasts for Clatsop County, located at latitude 46.188 and longitude -123.831. Stay updated with localized weather information tailored for Clatsop County.
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