S
M
T
W
T
F
S
30
82°
65°
31
78°
65°
1
80°
64°
2
83°
61°
3
83°
55°
4
75°
57°
5
74°
64°
6
80°
59°
7
79°
55°
8
73°
58°
9
72°
59°
10
74°
62°
11
76°
61°
12
81°
62°
13
80°
62°
14
81°
56°
15
79°
54°
16
71°
56°
17
71°
52°
18
72°
51°
19
70°
48°
20
69°
48°
21
67°
50°
22
68°
57°
23
70°
50°
24
71°
56°
25
74°
57°
26
70°
56°
27
76°
57°
28
75°
53°
29
74°
51°
30
67°
51°
1
68°
52°
2
73°
55°
3
66°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Long Grove
Long Grove's September 2026 forecast shows daily high temperatures ranging from 66° to 83°, with overnight lows between 45° and 65°. The average high for September is 74° with an average low of 56°. 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 Long Grove. See also: October | November | December.
