S
M
T
W
T
F
S
30
71°
60°
31
69°
56°
1
69°
54°
2
71°
60°
3
73°
61°
4
67°
56°
5
65°
59°
6
71°
61°
7
66°
58°
8
63°
54°
9
63°
57°
10
64°
57°
11
65°
58°
12
65°
56°
13
64°
58°
14
64°
59°
15
65°
58°
16
61°
48°
17
62°
49°
18
61°
48°
19
63°
53°
20
65°
54°
21
65°
54°
22
64°
53°
23
64°
53°
24
62°
52°
25
64°
53°
26
62°
52°
27
64°
52°
28
64°
51°
29
62°
53°
30
63°
51°
1
58°
50°
2
58°
48°
3
59°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Swansea
Swansea's September 2026 forecast shows daily high temperatures ranging from 58° to 73°, with overnight lows between 46° and 61°. The average high for September is 64° with an average low of 54°. 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 Swansea. See also: October | November | December.
