S
M
T
W
T
F
S
30
81°
62°
31
79°
61°
1
81°
57°
2
74°
55°
3
73°
57°
4
73°
56°
5
74°
53°
6
75°
60°
7
78°
60°
8
73°
59°
9
72°
59°
10
76°
58°
11
79°
59°
12
79°
58°
13
78°
59°
14
78°
49°
15
72°
49°
16
68°
50°
17
70°
48°
18
69°
47°
19
68°
49°
20
69°
51°
21
75°
54°
22
75°
54°
23
76°
47°
24
76°
45°
25
69°
45°
26
67°
48°
27
72°
52°
28
72°
52°
29
73°
46°
30
72°
45°
1
65°
45°
2
66°
46°
3
69°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Arlington Heights
Arlington Heights's September 2026 forecast shows daily high temperatures ranging from 65° to 81°, with overnight lows between 45° and 62°. The average high for September is 73° with an average low of 53°. 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 Arlington Heights. See also: October | November | December.
