Weather in San Diego in September
September in San Diego is mild with average temperatures around 23.4°C (74.1°F). Light rainfall with only 6mm expected.
Data Note: Temperature values are 2001–2020 satellite/reanalysis grid averages from NASA POWER and may differ from airport station normals by a few degrees.
Temperature
High
29.3°C
84.7°F
Low
17.5°C
63.5°F
Precipitation
6 mm
0.2 inches
~1 rainy days
Conditions
Humidity
57%
Comparison to Adjacent Months
September is 3.2°C warmer than October.