S
M
T
W
T
F
S
30
94°
74°
31
94°
75°
1
90°
75°
2
90°
75°
3
91°
76°
4
92°
75°
5
90°
76°
6
90°
74°
7
91°
76°
8
92°
75°
9
91°
76°
10
92°
77°
11
90°
76°
12
91°
74°
13
92°
75°
14
90°
77°
15
88°
77°
16
87°
76°
17
87°
77°
18
88°
77°
19
88°
76°
20
89°
77°
21
88°
77°
22
87°
76°
23
86°
75°
24
86°
75°
25
87°
77°
26
87°
77°
27
86°
76°
28
86°
76°
29
87°
75°
30
86°
76°
1
86°
75°
2
87°
75°
3
86°
74°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Dismal Key
Dismal Key's September 2026 forecast shows daily high temperatures ranging from 86° to 92°, with overnight lows between 74° and 77°. The average high for September is 89° with an average low of 76°. 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 Dismal Key. See also: October | November | December.
