S
M
T
W
T
F
S
30
93°
65°
31
91°
66°
1
94°
66°
2
96°
65°
3
94°
63°
4
100°
65°
5
98°
68°
6
88°
67°
7
101°
70°
8
91°
66°
9
84°
57°
10
87°
64°
11
100°
58°
12
87°
61°
13
75°
55°
14
74°
49°
15
76°
52°
16
82°
59°
17
81°
53°
18
77°
54°
19
73°
50°
20
72°
49°
21
85°
58°
22
84°
58°
23
84°
57°
24
83°
56°
25
74°
56°
26
79°
55°
27
82°
55°
28
80°
54°
29
76°
44°
30
67°
41°
1
65°
42°
2
65°
39°
3
66°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in McCook
McCook's September 2026 forecast shows daily high temperatures ranging from 65° to 101°, with overnight lows between 39° and 70°. The average high for September is 80° with an average low of 54°. 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 McCook. See also: October | November | December.
