S
M
T
W
T
F
S
30
95°
71°
31
95°
73°
1
96°
73°
2
95°
71°
3
93°
71°
4
89°
70°
5
91°
72°
6
93°
73°
7
95°
73°
8
95°
72°
9
94°
72°
10
94°
71°
11
93°
72°
12
93°
71°
13
92°
69°
14
86°
65°
15
85°
66°
16
87°
66°
17
90°
69°
18
89°
68°
19
84°
68°
20
86°
69°
21
91°
69°
22
90°
68°
23
89°
62°
24
90°
61°
25
82°
61°
26
83°
59°
27
88°
66°
28
88°
66°
29
89°
66°
30
Hist. Avg.
84°
59°
1
Hist. Avg.
84°
59°
2
Hist. Avg.
84°
58°
3
Hist. Avg.
83°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Sonoma
Sonoma's September 2026 forecast shows daily high temperatures ranging from 82° to 96°, with overnight lows between 59° and 73°. The average high for September is 90° with an average low of 68°. 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 Sonoma. See also: October | November | December.
