S
M
T
W
T
F
S
30
70°
53°
31
75°
48°
1
69°
49°
2
71°
51°
3
69°
56°
4
74°
55°
5
75°
55°
6
76°
54°
7
67°
48°
8
66°
48°
9
68°
50°
10
71°
54°
11
74°
54°
12
74°
55°
13
66°
55°
14
69°
56°
15
66°
54°
16
66°
54°
17
67°
51°
18
67°
53°
19
65°
51°
20
68°
47°
21
67°
46°
22
65°
47°
23
67°
49°
24
70°
51°
25
71°
52°
26
71°
48°
27
65°
52°
28
63°
43°
29
63°
46°
30
Hist. Avg.
66°
48°
1
Hist. Avg.
66°
48°
2
Hist. Avg.
65°
48°
3
Hist. Avg.
65°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Montesano
Montesano's September 2026 forecast shows daily high temperatures ranging from 63° to 76°, with overnight lows between 43° and 56°. The average high for September is 69° with an average low of 51°. 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 Montesano. See also: October | November | December.
