South San Francisco, CA Weather
South San Francisco, CA climate is mild during summer when temperatures tend to be in the 60's and cool during winter when temperatures tend to be in the 50's.
The warmest month of the year is September with an average maximum temperature of 72.70 degrees Fahrenheit, while the coldest month of the year is January with an average minimum temperature of 42.90 degrees Fahrenheit.
Temperature variations between night and day tend to be fairly limited during summer with a difference that can reach 16 degrees Fahrenheit, and fairly limited during winter with an average difference of 13 degrees Fahrenheit.
The annual average precipitation at South San Francisco is 20.11 Inches. Winter months tend to be wetter than summer months. The wettest month of the year is January with an average rainfall of 4.45 Inches.
Weather Data
Moon, Sunrise and Sunset
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Moon Phase: Waxing Gibbous Moon | Civil Twilight: 5:24 AM PDT |
Sunrise: 5:54 AM PDT |
| Sunset: 8:17 PM PDT |
Civil Twilight: 8:47 PM PDT |
Normal Climate
Normal Temperatures
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Max °F | 55.9 | 59.3 | 61.2 | 64.3 | 66.8 | 69.9 | 71.1 | 71.7 | 72.7 | 69.7 | 62.0 | 56.1 | 65.1 |
| Mean °F | 49.4 | 52.4 | 54.0 | 56.2 | 58.7 | 61.4 | 62.8 | 63.6 | 63.9 | 61.0 | 54.7 | 49.5 | 57.3 |
| Min °F | 42.9 | 45.5 | 46.8 | 48.1 | 50.5 | 52.9 | 54.5 | 55.5 | 55.1 | 52.4 | 47.5 | 43.0 | 49.6 |
Normal Precipitation
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inch | 4.45 | 4.01 | 3.26 | 1.18 | 0.38 | 0.11 | 0.03 | 0.07 | 0.20 | 1.04 | 2.49 | 2.89 | 20.11 |

