S
M
T
W
T
F
S
30
73°
48°
31
73°
47°
1
75°
47°
2
75°
46°
3
70°
43°
4
71°
40°
5
70°
38°
6
73°
43°
7
80°
46°
8
79°
45°
9
77°
46°
10
76°
45°
11
75°
45°
12
73°
44°
13
72°
42°
14
67°
36°
15
66°
35°
16
70°
40°
17
74°
44°
18
75°
40°
19
64°
37°
20
62°
32°
21
71°
37°
22
66°
34°
23
67°
33°
24
64°
30°
25
69°
35°
26
68°
36°
27
66°
39°
28
70°
27°
29
60°
24°
30
56°
26°
1
58°
27°
2
61°
30°
3
65°
30°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Alta
Alta's September 2026 forecast shows daily high temperatures ranging from 56° to 80°, with overnight lows between 24° and 48°. The average high for September is 69° with an average low of 38°. 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 Alta. See also: October | November | December.
