S
M
T
W
T
F
S
30
67°
48°
31
66°
49°
1
65°
52°
2
65°
51°
3
62°
52°
4
62°
51°
5
64°
48°
6
65°
52°
7
64°
49°
8
61°
48°
9
64°
50°
10
65°
51°
11
65°
50°
12
63°
51°
13
61°
51°
14
59°
46°
15
59°
46°
16
60°
45°
17
59°
45°
18
58°
46°
19
58°
47°
20
59°
46°
21
59°
46°
22
60°
48°
23
59°
47°
24
58°
46°
25
58°
47°
26
59°
45°
27
Hist. Avg.
58°
48°
28
Hist. Avg.
58°
47°
29
Hist. Avg.
58°
47°
30
Hist. Avg.
58°
47°
1
Hist. Avg.
57°
47°
2
Hist. Avg.
57°
47°
3
Hist. Avg.
57°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Dunoon
Dunoon's September 2026 forecast shows daily high temperatures ranging from 58° to 67°, with overnight lows between 45° and 52°. The average high for September is 62° with an average low of 48°. 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 Dunoon. See also: October | November | December.