S
M
T
W
T
F
S
30
83°
69°
31
86°
69°
1
95°
72°
2
93°
73°
3
91°
72°
4
92°
70°
5
83°
66°
6
81°
64°
7
81°
67°
8
85°
67°
9
85°
63°
10
80°
60°
11
76°
58°
12
76°
58°
13
74°
59°
14
75°
58°
15
74°
53°
16
78°
59°
17
77°
58°
18
70°
57°
19
74°
58°
20
75°
57°
21
74°
57°
22
73°
55°
23
69°
55°
24
71°
53°
25
74°
55°
26
74°
50°
27
64°
46°
28
62°
43°
29
63°
46°
30
62°
43°
1
61°
45°
2
64°
52°
3
63°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Island Lake
Island Lake's September 2026 forecast shows daily high temperatures ranging from 61° to 93°, with overnight lows between 43° and 73°. The average high for September is 75° with an average low of 57°. 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 Island Lake. See also: October | November | December.
