S
M
T
W
T
F
S
30
79°
52°
31
79°
54°
1
78°
54°
2
78°
53°
3
79°
55°
4
78°
55°
5
78°
53°
6
79°
53°
7
85°
49°
8
84°
48°
9
82°
48°
10
81°
47°
11
80°
48°
12
81°
49°
13
80°
49°
14
81°
53°
15
80°
54°
16
81°
54°
17
85°
53°
18
86°
54°
19
85°
54°
20
86°
53°
21
86°
53°
22
85°
52°
23
81°
53°
24
81°
52°
25
79°
53°
26
84°
53°
27
85°
52°
28
84°
50°
29
84°
52°
30
83°
53°
1
84°
54°
2
86°
53°
3
85°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Cotati
Cotati's September 2026 forecast shows daily high temperatures ranging from 78° to 86°, with overnight lows between 47° and 55°. The average high for September is 82° with an average low of 52°. 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 Cotati. See also: October | November | December.
