S
M
T
W
T
F
S
30
75°
50°
31
74°
49°
1
72°
55°
2
72°
49°
3
73°
48°
4
72°
56°
5
72°
56°
6
79°
49°
7
76°
47°
8
68°
48°
9
68°
51°
10
70°
53°
11
70°
52°
12
67°
50°
13
75°
52°
14
68°
43°
15
67°
42°
16
Hist. Avg.
70°
48°
17
Hist. Avg.
70°
48°
18
Hist. Avg.
69°
47°
19
Hist. Avg.
69°
47°
20
Hist. Avg.
68°
46°
21
Hist. Avg.
68°
46°
22
Hist. Avg.
68°
45°
23
Hist. Avg.
67°
45°
24
Hist. Avg.
67°
44°
25
Hist. Avg.
66°
44°
26
Hist. Avg.
66°
43°
27
Hist. Avg.
66°
43°
28
Hist. Avg.
65°
42°
29
Hist. Avg.
65°
42°
30
Hist. Avg.
64°
41°
1
Hist. Avg.
64°
41°
2
Hist. Avg.
63°
40°
3
Hist. Avg.
63°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Cosmos
Cosmos's September 2026 forecast shows daily high temperatures ranging from 67° to 79°, with overnight lows between 42° and 56°. 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 Cosmos. See also: October | November | December.
