Idyllwild Weather in September

The climate in Idyllwild during September can be summarized as warm and dry.

September is in the fall / autumn in Idyllwild and is typically the 3rd warmest month of the year. Daytime maximum temperatures average around a comfortable 27°C (80°F), whilst at night 10°C (50°F) is normal.

On average September is the 3rd driest month of the year in Idyllwild with around 22mm 0.8 inches of rain making it a dry time to visit. This rainfall is typically spread over 3 days, although this may vary considerably.

On the flip side this corresponds to an average of 10.1 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 Idyllwild in September 2025.