S
M
T
W
T
F
S
30
72°
54°
31
73°
55°
1
71°
54°
2
69°
50°
3
66°
49°
4
66°
49°
5
68°
50°
6
70°
51°
7
70°
52°
8
71°
53°
9
71°
55°
10
70°
53°
11
69°
52°
12
67°
53°
13
68°
50°
14
64°
47°
15
64°
48°
16
65°
47°
17
66°
48°
18
65°
51°
19
66°
48°
20
63°
46°
21
63°
46°
22
64°
51°
23
66°
51°
24
68°
50°
25
68°
47°
26
65°
47°
27
63°
49°
28
62°
50°
29
63°
49°
30
63°
45°
1
62°
46°
2
61°
44°
3
61°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Southampton
Southampton's September 2026 forecast shows daily high temperatures ranging from 61° to 73°, with overnight lows between 43° and 55°. The average high for September is 66° with an average low of 50°. 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 Southampton. See also: October | November | December.
