S
M
T
W
T
F
S
30
72°
55°
31
77°
57°
1
76°
53°
2
70°
53°
3
72°
54°
4
75°
54°
5
75°
53°
6
74°
56°
7
76°
56°
8
76°
57°
9
75°
57°
10
73°
55°
11
74°
56°
12
70°
55°
13
68°
53°
14
71°
51°
15
72°
52°
16
72°
47°
17
69°
47°
18
71°
48°
19
71°
48°
20
70°
50°
21
70°
46°
22
66°
45°
23
64°
49°
24
63°
46°
25
64°
45°
26
63°
49°
27
66°
50°
28
66°
45°
29
65°
47°
30
65°
44°
1
64°
51°
2
68°
51°
3
68°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Siersburg
Siersburg's September 2026 forecast shows daily high temperatures ranging from 63° to 77°, with overnight lows between 44° and 57°. The average high for September is 70° with an average low of 51°. 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 Siersburg. See also: October | November | December.
