S
M
T
W
T
F
S
30
97°
70°
31
96°
70°
1
93°
69°
2
98°
68°
3
97°
68°
4
95°
67°
5
90°
67°
6
91°
66°
7
94°
67°
8
97°
68°
9
97°
68°
10
96°
67°
11
96°
67°
12
95°
66°
13
95°
65°
14
87°
62°
15
87°
59°
16
88°
65°
17
92°
63°
18
94°
60°
19
93°
59°
20
92°
60°
21
94°
63°
22
91°
57°
23
90°
59°
24
91°
62°
25
91°
65°
26
93°
64°
27
92°
65°
28
93°
62°
29
91°
60°
30
91°
57°
1
89°
57°
2
81°
51°
3
80°
49°
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 80° to 98°, with overnight lows between 49° and 70°. The average high for September is 92° with an average low of 63°. 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.
