The weather in San Diego in September is hot. The average temperatures are between 20°C and 27°C.
You can expect a few rainy days in San Diego during September, but usually the weather is comfortable in September.
Our weather forecast can give you a great sense of what weather to expect in San Diego in September 2025.
If you’re planning to visit San Diego in the near future, we highly recommend that you review the 14 day weather forecast for San Diego before you arrive.
Temperatures
27° / 20°
Rainy Days
1
Snowy Days
0
Dry Days
29
Rainfall
15
mm
Sun Hours
11.8
Hrs
