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Current
Hourly
7 Days
14 Days
Weekend
Monthly
Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
South San Francisco, CA
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May
Average Temperature
High
17°
Feels 17
Low
10°
Feels 8
Average Precipitation
2 Days
Rain amount
7.2mm
Snow amount
0cm
Content continues below
Daily Historical Averages
May 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
25°
19
24°
20
21°
21
20°
22
16°
23
18°
24
18°
25
17°
26
18°
27
17°
28
17°
29
17°
30
18°
31
18°
Forecast
Monday, May 18, 2026
Day
25°
Feels 25
Wind
38 km/h W
Gust
57 km/h
Humidity
29%
P.O.P
0%
Night
11°
Feels 11
Wind
26 km/h W
Gust
39 km/h
Humidity
83%
P.O.P
0%
Historical Averages
May 18
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.