S
M
T
W
T
F
S
30
70°
61°
31
66°
57°
1
68°
54°
2
68°
55°
3
72°
57°
4
79°
61°
5
68°
54°
6
72°
50°
7
82°
61°
8
79°
59°
9
69°
49°
10
69°
44°
11
71°
49°
12
74°
52°
13
71°
57°
14
73°
49°
15
77°
53°
16
69°
49°
17
69°
48°
18
71°
48°
19
74°
50°
20
75°
50°
21
73°
51°
22
68°
53°
23
69°
50°
24
70°
52°
25
69°
49°
26
62°
47°
27
62°
52°
28
64°
45°
29
60°
44°
30
58°
45°
1
58°
45°
2
59°
43°
3
61°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Sankt Sebastian
Sankt Sebastian's September 2026 forecast shows daily high temperatures ranging from 58° to 77°, with overnight lows between 43° and 57°. The average high for September is 68° with an average low of 49°. 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 Sankt Sebastian. See also: October | November | December.
