Weather in Eureka, California for September 2026
Small Craft Advisory - See hour by hour.
Until now, September 2026 in Eureka has been nearly identical to the historical average, with a temperature of 17.4 °F (showing only a slight deviation of 0.5 °F).
The forecast for the upcoming days in Eureka predicts a temperature of 16.1 °F, which is slightly above the historical average.
In general, the average temperature in Eureka at the beginning of September is 17.6 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 15.3 °F by the end of September.
With an average of 5 rainy days, Eureka experiences minimal rainfall in September.
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Eureka Weather September
Temperatures trend during September in Eureka
September weather in Eureka day by day
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Patchy rain possible | 17° /12° | 4.3 mm | 3 | |
| Sept. 2 | Patchy rain possible | 16° /12° | 22.7 mm | 3 | |
| Sept. 3 | Patchy rain possible | 17° /12° | 0.4 mm | 4 | |
| Sept. 4 | Patchy rain possible | 19° /12° | 0 mm | 6 | |
| Sept. 5 |  Sunny | 18° /12° | 0 mm | 5 | |
| Sept. 6 | Patchy rain possible | 17° /12° | 0.1 mm | 5 | |
| Sept. 7 | Patchy rain possible | 19° /12° | 0.2 mm | 3 | |
| Sept. 8 | Patchy rain possible | 20° /11° | 0 mm | 4 | |
| Sept. 9 | Patchy rain possible | 19° /12° | 0 mm | 5 | |
| Sept. 10 |  Partly cloudy | 16° /12° | 0 mm | 3 | |
| Sept. 11 | Light rain shower | 16° /11° | 0.7 mm | 3 | |
| Sept. 12 | Patchy rain possible | 16° /10° | 0.1 mm | 4 | |
| Sept. 13 | Patchy rain possible | 16° /11° | 0.4 mm | 5 | |
| Sept. 14 |  Overcast | 16° /11° | 0.9 mm | 5 | |
| Sept. 15 | Patchy rain possible | 16° /11° | 0.2 mm | 5 | |
| Sept. 16 | Patchy rain possible | 17° /11° | 0.1 mm | 5 | |
| Sept. 17 |  Fog | 15° /12° | 3.8 mm | 4 | |
| Sept. 18 | Fog | 16° /12° | 0 mm | 5 | |
| Sept. 19 | Fog | 15° /12° | 0.2 mm | 4 | |
| Sept. 20 | Mist | 16° /12° | 0.4 mm | 3 | |
| Sept. 21 | Patchy rain possible | 15° /13° | 0.4 mm | 4.7 | |
| Sept. 22 | Patchy rain possible | 15° /14° | 0.1 mm | 5.3 | |
| Sept. 23 | Sunny | 16° /12° | 0 mm | 5.8 | |
| Sept. 24 | Overcast | 17° /12° | 0 mm | 5.1 | |
| Sept. 25 | Patchy rain possible | 15° /12° | 0.4 mm | 4.8 | |
| Sept. 26 | Sunny | 15° /11° | 0 mm | 4 | |
| Sept. 27 | Patchy rain possible | 15° /10° | 0.8 mm | 4 | |
| Sept. 28 | Sunny | 15° /11° | 0 mm | 4 | |
| Sept. 29 | Overcast | 15° /11° | 0 mm | 4 | |
| Sept. 30 | Sunny | 15° /11° | 0 mm | 5 | |
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Eureka in September - FAQ
What are the expected maximum and minimum temperatures in Eureka during September?
How much rainfall should be expected in Eureka during September?
What are the typical wind conditions in Eureka during September?
September rainfall patterns in Eureka
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Where is Eureka?Get accurate weather forecasts for Eureka, located at latitude 40.802 and longitude -124.164. Stay updated with localized weather information tailored for Eureka.