Eureka Weather in September

The climate in Eureka during September can be summarized as warm and damp.

September is in the fall / autumn in Eureka and is typically the 4th warmest month of the year. Daytime maximum temperatures average around a comfortable 28°C (81°F), whilst at night 15°C (58°F) is normal.

On average September is the 3rd wettest month of the year in Eureka with around 104mm 4.1 inches of rain making it a damp time to visit. This rainfall is typically spread over 8 days, although this may vary considerably.

On the flip side this corresponds to an average of 8.5 hours of sunshine per day.

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Eureka in September 2025.