Month-by-month travel weather
San Diego September weather
San Diego, United States · September
Coastal vs inland differences remain
September often stays warm and dry, making outdoor plans easy.
Inland day trips can feel hotter than the coast, while coastal evenings can cool down—thin layers help.
September averages at a glance
Average low
around 18–20°C
Average high
around 25–28°C
Average precipitation
around 0–10 mm
Rainy days
about 0–2 days
What to wear in September in San Diego
Actual feel will change with wind and rain, but use the suggestions below to build a comfortable layered outfit.
- • Breathable clothing + sun protection works well.
- • Optional thin layer for coastal evenings.
- • Hydration option helps.
Travel tips for visiting San Diego in September
- • Treat inland routes like one step hotter.
- • Beach evenings can feel cooler than midday.
September weather in San Diego — FAQ
Q. Does September feel like summer?
A. Often yes, though late hours can be cooler on the coast.
Q. Does it rain?
A. Usually very little, though occasional showers are possible.
Explore San Diego
These pages are connected so you can compare conditions and decide for yourself.