S
M
T
W
T
F
S
30
63°
46°
31
64°
47°
1
62°
57°
2
65°
59°
3
64°
53°
4
66°
54°
5
55°
44°
6
58°
45°
7
53°
47°
8
61°
52°
9
72°
56°
10
73°
53°
11
69°
51°
12
63°
50°
13
60°
51°
14
61°
47°
15
61°
50°
16
58°
50°
17
62°
49°
18
61°
49°
19
58°
48°
20
59°
50°
21
60°
50°
22
61°
49°
23
58°
47°
24
56°
45°
25
55°
45°
26
56°
44°
27
55°
45°
28
56°
46°
29
57°
45°
30
56°
48°
1
56°
43°
2
57°
45°
3
60°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mendocino
Mendocino's September 2026 forecast shows daily high temperatures ranging from 53° to 73°, with overnight lows between 43° and 59°. The average high for September is 60° with an average low of 49°. 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 Mendocino. See also: October | November | December.
