S
M
T
W
T
F
S
30
91°
71°
31
92°
70°
1
92°
70°
2
90°
69°
3
87°
70°
4
88°
66°
5
85°
66°
6
86°
68°
7
85°
68°
8
88°
67°
9
89°
68°
10
85°
68°
11
85°
63°
12
87°
67°
13
90°
66°
14
87°
60°
15
84°
60°
16
83°
61°
17
82°
60°
18
84°
61°
19
88°
61°
20
88°
65°
21
87°
65°
22
86°
64°
23
87°
65°
24
85°
61°
25
85°
60°
26
86°
60°
27
86°
59°
28
85°
62°
29
86°
62°
30
86°
61°
1
85°
61°
2
85°
60°
3
84°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Shannon
Shannon's September 2026 forecast shows daily high temperatures ranging from 82° to 92°, with overnight lows between 55° and 71°. The average high for September is 87° with an average low of 64°. 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 Shannon. See also: October | November | December.
