S
M
T
W
T
F
S
30
83°
55°
31
81°
63°
1
90°
68°
2
87°
67°
3
87°
69°
4
81°
63°
5
80°
55°
6
74°
57°
7
76°
58°
8
71°
57°
9
72°
56°
10
75°
57°
11
73°
56°
12
71°
55°
13
71°
53°
14
72°
54°
15
73°
58°
16
71°
57°
17
73°
51°
18
67°
48°
19
68°
49°
20
72°
56°
21
75°
57°
22
75°
57°
23
76°
56°
24
75°
54°
25
74°
53°
26
72°
53°
27
74°
54°
28
74°
54°
29
73°
51°
30
68°
47°
1
65°
45°
2
68°
51°
3
71°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Altoona
Altoona's September 2026 forecast shows daily high temperatures ranging from 65° to 90°, with overnight lows between 45° and 69°. The average high for September is 74° with an average low of 55°. 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 Altoona. See also: October | November | December.
