S
M
T
W
T
F
S
30
68°
56°
31
71°
58°
1
72°
58°
2
72°
57°
3
68°
58°
4
67°
58°
5
71°
57°
6
73°
59°
7
73°
58°
8
72°
59°
9
73°
55°
10
68°
51°
11
67°
51°
12
68°
52°
13
67°
55°
14
66°
54°
15
70°
53°
16
72°
56°
17
71°
59°
18
73°
60°
19
66°
60°
20
67°
59°
21
73°
59°
22
73°
58°
23
71°
59°
24
72°
59°
25
73°
58°
26
73°
59°
27
72°
58°
28
68°
58°
29
68°
59°
30
69°
59°
1
74°
60°
2
75°
59°
3
74°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in San Francisco
San Francisco's September 2026 forecast shows daily high temperatures ranging from 66° to 75°, with overnight lows between 51° and 60°. The average high for September is 71° with an average low of 57°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in San Francisco. See also: October | November | December.
