S
M
T
W
T
F
S
30
87°
68°
31
90°
69°
1
93°
71°
2
94°
72°
3
96°
72°
4
96°
71°
5
94°
69°
6
88°
68°
7
87°
67°
8
90°
68°
9
91°
69°
10
92°
71°
11
82°
63°
12
84°
64°
13
86°
65°
14
86°
66°
15
87°
67°
16
87°
68°
17
86°
68°
18
85°
67°
19
86°
67°
20
87°
66°
21
87°
67°
22
86°
67°
23
85°
65°
24
86°
66°
25
86°
65°
26
83°
64°
27
83°
63°
28
82°
62°
29
82°
62°
30
81°
61°
1
83°
62°
2
83°
62°
3
84°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Duncan
Duncan's September 2026 forecast shows daily high temperatures ranging from 81° to 96°, with overnight lows between 61° and 72°. The average high for September is 87° with an average low of 66°. 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 Duncan. See also: October | November | December.
