S
M
T
W
T
F
S
30
84°
66°
31
84°
64°
1
84°
59°
2
84°
64°
3
88°
68°
4
84°
64°
5
84°
63°
6
75°
66°
7
81°
64°
8
84°
64°
9
75°
57°
10
79°
54°
11
84°
63°
12
70°
55°
13
70°
47°
14
63°
51°
15
69°
49°
16
67°
50°
17
70°
56°
18
66°
54°
19
70°
51°
20
69°
48°
21
70°
47°
22
70°
50°
23
71°
53°
24
72°
51°
25
74°
50°
26
67°
43°
27
72°
52°
28
62°
49°
29
66°
48°
30
67°
44°
1
70°
47°
2
65°
47°
3
69°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Cosmos
Cosmos's September 2026 forecast shows daily high temperatures ranging from 62° to 74°, with overnight lows between 43° and 56°. The average high for September is 69° with an average low of 49°. 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 Cosmos. See also: October | November | December.
