S
M
T
W
T
F
S
30
94°
74°
31
94°
74°
1
91°
75°
2
95°
75°
3
95°
76°
4
94°
75°
5
96°
75°
6
94°
76°
7
94°
76°
8
93°
75°
9
94°
76°
10
94°
76°
11
93°
75°
12
94°
76°
13
93°
75°
14
93°
75°
15
91°
74°
16
90°
75°
17
91°
74°
18
92°
74°
19
92°
69°
20
88°
71°
21
86°
73°
22
88°
74°
23
89°
74°
24
90°
73°
25
91°
74°
26
92°
73°
27
92°
72°
28
91°
73°
29
90°
72°
30
89°
72°
1
Hist. Avg.
88°
70°
2
Hist. Avg.
88°
70°
3
Hist. Avg.
88°
69°
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 86° to 96°, with overnight lows between 69° and 76°. The average high for September is 92° with an average low of 74°. 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.
