S
M
T
W
T
F
S
30
73°
52°
31
74°
52°
1
73°
53°
2
73°
52°
3
74°
52°
4
75°
51°
5
75°
52°
6
74°
54°
7
72°
52°
8
73°
50°
9
71°
51°
10
72°
48°
11
71°
48°
12
71°
49°
13
73°
53°
14
71°
50°
15
76°
54°
16
77°
55°
17
77°
55°
18
76°
52°
19
77°
45°
20
70°
46°
21
67°
52°
22
68°
51°
23
72°
52°
24
74°
53°
25
73°
44°
26
72°
41°
27
66°
44°
28
64°
43°
29
64°
43°
30
63°
41°
1
Hist. Avg.
68°
45°
2
Hist. Avg.
67°
45°
3
Hist. Avg.
67°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Clear Lake
Clear Lake's September 2026 forecast shows daily high temperatures ranging from 63° to 77°, with overnight lows between 41° and 55°. The average high for September is 72° with an average low of 50°. 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 Clear Lake. See also: October | November | December.
