Annual mean 13°C · wettest around March · prevailing wind W
Warmest
19.9 °C
Coldest
12.6 °C
Wettest
86%
Windiest
5.1 m/s
Prevailing
W
4.3 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in South San Francisco over the whole year is 13°C. September is the hottest month, with highs of about 19°C; February is the coldest, with lows of about 8°C. The rainy (wet) season in South San Francisco runs from October to May, peaking in March with a 86% chance of rain on a given day. The dry season is June to September; June is the driest month, at 37%. Winds in South San Francisco are highest in May, averaging 3.7 m/s (13 km/h), and lightest in October, at 2.5 m/s (9 km/h). The prevailing wind is from the W. The clearest skies in South San Francisco come in November, when the sky is typically 38% covered; July is the cloudiest month, at 56%.
Month by month South San Francisco climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
13°C
9°C
10°C
85%
52%
2.9 m/s
12
0
72
February
14°C
8°C
10°C
85%
39%
3.3 m/s
16
0
68
March
14°C
9°C
10°C
86%
51%
3.5 m/s
13
0
70
April
15°C
10°C
12°C
84%
45%
3.6 m/s
23
1
76
May
16°C
12°C
13°C
83%
50%
3.7 m/s
28
3
79
June
17°C
13°C
15°C
37%
45%
3.7 m/s
37
7
78
July
18°C
14°C
16°C
54%
56%
3.4 m/s
49
10
77
August
19°C
14°C
18°C
51%
56%
3.1 m/s
67
11
75
September
19°C
14°C
18°C
53%
47%
2.9 m/s
65
10
76
October
19°C
12°C
17°C
78%
39%
2.5 m/s
59
8
77
November
16°C
10°C
13°C
84%
38%
2.6 m/s
30
0
80
December
13°C
9°C
11°C
85%
45%
2.8 m/s
13
0
73
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short South San Francisco weather by season
Year round, South San Francisco has days of about 13°C at their warmest in January, its coolest month, and 19°C in September, its warmest; the coolest hours of the day run from 8°C to 14°C through the year, and the average temperature over the year is 13°C around the clock. Rain is most likely around March and least likely around June. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
South San Francisco weather in winterDecember to February
High 13°CLow 9°CRain 85%
Winter in South San Francisco has typical daily highs of about 13°C and lows of about 9°C, with a 85% chance of rain on a given day.
South San Francisco weather in springMarch to May
High 15°CLow 10°CRain 84%
Spring in South San Francisco has typical daily highs of about 15°C and lows of about 10°C, with a 84% chance of rain on a given day.
South San Francisco weather in summerJune to August
High 18°CLow 14°CRain 47%
Summer in South San Francisco has typical daily highs of about 18°C and lows of about 14°C, with a 47% chance of rain on a given day.
South San Francisco weather in autumnSeptember to November
High 18°CLow 12°CRain 72%
Autumn in South San Francisco has typical daily highs of about 18°C and lows of about 12°C, with a 72% chance of rain on a given day.
When is the rainy season in South San Francisco?
The rainy (wet) season in South San Francisco runs from October to May, peaking in March with a 86% chance of rain on a given day. The dry season is June to September; June is the driest month, at 37%.
What time of year is South San Francisco windiest?
Winds in South San Francisco are highest in May, averaging 3.7 m/s (13 km/h), and lightest in October, at 2.5 m/s (9 km/h). The prevailing wind is from the W.
What is the average temperature in South San Francisco year round?
The average temperature in South San Francisco over the whole year is 13°C. September is the hottest month, with highs of about 19°C; February is the coldest, with lows of about 8°C.