S
M
T
W
T
F
S
30
101°
74°
31
101°
71°
1
102°
70°
2
101°
74°
3
99°
74°
4
100°
72°
5
102°
71°
6
104°
71°
7
102°
74°
8
103°
76°
9
104°
75°
10
79°
65°
11
90°
63°
12
92°
70°
13
87°
68°
14
96°
75°
15
98°
76°
16
97°
73°
17
97°
72°
18
96°
71°
19
97°
68°
20
87°
66°
21
80°
59°
22
76°
57°
23
79°
63°
24
76°
57°
25
78°
56°
26
81°
61°
27
84°
60°
28
83°
58°
29
80°
58°
30
84°
53°
1
78°
60°
2
72°
60°
3
77°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Dennis
Dennis's September 2026 forecast shows daily high temperatures ranging from 72° to 97°, with overnight lows between 53° and 72°. The average high for September is 83° with an average low of 61°. 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 Dennis. See also: October | November | December.
