October Weather in San Diego is similar to September because it can get hot when the Santa Ana winds are blowing. Temperatures as high as 107°F have been measured in San Diego in October. Still, the high averages a mild 74°F and the low averages 61.
San Diego averages 2 days of rain in October, and the normal total rainfall is .44 inches. While these numbers are low this is higher than the past 4 months.