S
M
T
W
T
F
S
30
91°
70°
31
91°
69°
1
90°
70°
2
91°
70°
3
92°
69°
4
92°
70°
5
93°
70°
6
89°
69°
7
87°
70°
8
91°
71°
9
90°
70°
10
92°
71°
11
91°
69°
12
89°
65°
13
86°
64°
14
87°
62°
15
86°
63°
16
85°
63°
17
86°
64°
18
88°
64°
19
87°
63°
20
Hist. Avg.
87°
65°
21
Hist. Avg.
87°
64°
22
Hist. Avg.
87°
64°
23
Hist. Avg.
86°
64°
24
Hist. Avg.
86°
64°
25
Hist. Avg.
86°
63°
26
Hist. Avg.
86°
63°
27
Hist. Avg.
85°
63°
28
Hist. Avg.
85°
63°
29
Hist. Avg.
85°
62°
30
Hist. Avg.
85°
62°
1
Hist. Avg.
84°
62°
2
Hist. Avg.
84°
62°
3
Hist. Avg.
84°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in San Francisco
San Francisco's September 2026 forecast shows daily high temperatures ranging from 85° to 93°, with overnight lows between 62° and 71°. The average high for September is 89° with an average low of 67°. 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.
