Joshua Tree Weather in September

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

September is in the fall / autumn in Joshua Tree and is typically the 4th warmest month of the year. Daytime maximum temperatures average around a comfortable 31°C (89°F), whilst at night 14°C (58°F) is normal.

On average September is the 5th driest month of the year in Joshua Tree with around 16mm 0.6 inches of rain making it a dry time to visit. This rainfall is typically spread over 2 days, although this may vary considerably.

On the flip side this corresponds to an average of 10.8 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 Joshua Tree in September 2025.