S
M
T
W
T
F
S
30
71°
52°
31
77°
55°
1
77°
55°
2
76°
54°
3
77°
47°
4
73°
46°
5
71°
46°
6
69°
48°
7
68°
47°
8
67°
48°
9
68°
48°
10
67°
51°
11
67°
51°
12
73°
54°
13
73°
53°
14
65°
44°
15
64°
43°
16
Hist. Avg.
67°
50°
17
Hist. Avg.
67°
50°
18
Hist. Avg.
67°
50°
19
Hist. Avg.
66°
50°
20
Hist. Avg.
66°
49°
21
Hist. Avg.
66°
49°
22
Hist. Avg.
66°
49°
23
Hist. Avg.
65°
49°
24
Hist. Avg.
65°
48°
25
Hist. Avg.
65°
48°
26
Hist. Avg.
64°
48°
27
Hist. Avg.
64°
48°
28
Hist. Avg.
63°
47°
29
Hist. Avg.
63°
47°
30
Hist. Avg.
63°
47°
1
Hist. Avg.
62°
47°
2
Hist. Avg.
62°
46°
3
Hist. Avg.
62°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Altdorf
Altdorf's September 2026 forecast shows daily high temperatures ranging from 64° to 77°, with overnight lows between 43° and 55°. The average high for September is 71° 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 Altdorf. See also: October | November | December.
