S
M
T
W
T
F
S
30
101°
77°
31
102°
78°
1
101°
77°
2
100°
74°
3
92°
75°
4
100°
73°
5
101°
76°
6
101°
74°
7
103°
78°
8
102°
76°
9
100°
75°
10
97°
74°
11
98°
75°
12
100°
75°
13
98°
73°
14
98°
71°
15
94°
70°
16
91°
69°
17
89°
68°
18
90°
67°
19
88°
64°
20
86°
64°
21
87°
63°
22
92°
70°
23
91°
69°
24
90°
68°
25
84°
68°
26
88°
67°
27
89°
67°
28
88°
66°
29
87°
67°
30
86°
61°
1
78°
55°
2
76°
56°
3
75°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Cooper
Cooper's September 2026 forecast shows daily high temperatures ranging from 75° to 102°, with overnight lows between 55° and 76°. The average high for September is 90° with an average low of 67°. 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 Cooper. See also: October | November | December.
