S
M
T
W
T
F
S
30
82°
62°
31
79°
61°
1
77°
66°
2
76°
61°
3
78°
57°
4
76°
62°
5
76°
66°
6
83°
65°
7
84°
66°
8
83°
64°
9
83°
61°
10
76°
63°
11
76°
62°
12
73°
64°
13
82°
61°
14
72°
54°
15
71°
52°
16
Hist. Avg.
76°
57°
17
Hist. Avg.
75°
57°
18
Hist. Avg.
75°
56°
19
Hist. Avg.
74°
56°
20
Hist. Avg.
74°
55°
21
Hist. Avg.
74°
55°
22
Hist. Avg.
73°
55°
23
Hist. Avg.
73°
54°
24
Hist. Avg.
72°
54°
25
Hist. Avg.
72°
53°
26
Hist. Avg.
72°
53°
27
Hist. Avg.
71°
52°
28
Hist. Avg.
71°
52°
29
Hist. Avg.
70°
52°
30
Hist. Avg.
70°
51°
1
Hist. Avg.
69°
51°
2
Hist. Avg.
69°
50°
3
Hist. Avg.
68°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in O'Hare
O'Hare's September 2026 forecast shows daily high temperatures ranging from 71° to 84°, with overnight lows between 52° and 66°. The average high for September is 78° with an average low of 62°. 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 O'Hare. See also: October | November | December.
