Humboldt County (Eureka)
September
Weather in Humboldt County, California for September 2025
Your guide to Humboldt County weather in September - trends and predictions
Until now, September 2025 in Humboldt County is slightly cooler than the historical average by -1.3 °F.
The forecast for the next days in Humboldt County predicts temperatures to be around 18 °F, close to the historical average.
In general, the average temperature in Humboldt County at the beginning of September is 17.1 °F. As the month progressed, temperatures tended to slightly decrease, reaching an average of 17 °F by the end of September.
With an average of 2 rainy days, Humboldt County experiences minimal rainfall in September.
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Temperatures
Rain 🌧️
More
28
Dry days
2
Rainy days
0
Snow days
17°/11°
Temperatures
13 km/h
Avg max wind
84 %
Avg humidity
Humboldt County Weather September
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Temperatures trend during September in Humboldt County
See the weather trend as well as the moving average line
September weather in Humboldt County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Patchy rain possible | 16° /11° | 0.1 mm | 4 | |
| Sept. 2 | Patchy rain possible | 16° /11° | 0 mm | 4 | |
| Sept. 3 | Patchy rain possible | 17° /12° | 0 mm | 4 | |
| Sept. 4 | Patchy rain possible | 18° /13° | 0 mm | 5 | |
| Sept. 5 |  Sunny | 18° /14° | 0 mm | 5 | |
| Sept. 6 | Patchy rain possible | 17° /13° | 0.1 mm | 4 | |
| Sept. 7 | Patchy rain possible | 18° /13° | 0.2 mm | 4 | |
| Sept. 8 | Patchy rain possible | 18° /12° | 0 mm | 4 | |
| Sept. 9 | Patchy rain possible | 17° /13° | 0.1 mm | 4 | |
| Sept. 10 |  Partly cloudy | 16° /12° | 0 mm | 5 | |
| Sept. 11 | Light rain shower | 15° /11° | 1.1 mm | 4 | |
| Sept. 12 | Patchy rain possible | 15° /11° | 0 mm | 4 | |
| Sept. 13 | Patchy rain possible | 16° /12° | 0 mm | 4 | |
| Sept. 14 |  Overcast | 16° /12° | 1.4 mm | 4 | |
| Sept. 15 | Patchy rain possible | 16° /12° | 0.3 mm | 5 | |
| Sept. 16 | Patchy rain possible | 17° /11° | 0.1 mm | 5 | |
| Sept. 17 |  Cloudy | 16° /13° | 0 mm | 1.6 | |
| Sept. 18 |  Mist | 16° /14° | 0 mm | 1.4 | |
| Sept. 19 |  Moderate rain | 20° /14° | 6.5 mm | 1.4 | |
| Sept. 20 | Fog | 19° /12° | 0 mm | 1.4 | |
| Sept. 21 | Sunny | 19° /12° | 0.1 mm | 0 | |
| Sept. 22 | Sunny | 19° /13° | 0 mm | 5 | |
| Sept. 23 | Partly cloudy | 17° /13° | 0 mm | 4 | |
| Sept. 24 | Patchy rain possible | 16° /11° | 4.5 mm | 3 | |
| Sept. 25 | Patchy rain possible | 19° /10° | 4.2 mm | 3 | |
| Sept. 26 | Patchy rain possible | 18° /12° | 1.7 mm | 3 | |
| Sept. 27 | Patchy rain possible | 18° /11° | 1.5 mm | 3 | |
| Sept. 28 | Sunny | 17° /11° | 0 mm | 4 | |
| Sept. 29 | Sunny | 16° /10° | 0 mm | 4 | |
| Sept. 30 | Sunny | 15° /10° | 0 mm | 4 | |
| Next | |||||
Important Notice
Our weather forecast for Humboldt 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 Humboldt County forecast closer to your planned date for the most up-to-date weather information.
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Humboldt County in September - FAQ
What are the expected maximum and minimum temperatures in Humboldt County during September?
Enjoy moderate daytime temperatures of up to 17° and cooler nights around 11°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Humboldt County during September?
Expect minimal rainfall in Humboldt County during September, with a total of 15.5 mm over approximately 2 days. This minimal precipitation is unlikely to significantly impact plans.
What are the typical wind conditions in Humboldt County during September?
The average wind speed in Humboldt County during September is 13 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Humboldt County
Explore the daily rainfall trends and prepare for Humboldt Countys September weather 💧
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