S
M
T
W
T
F
S
30
75°
65°
31
76°
66°
1
77°
65°
2
76°
61°
3
77°
60°
4
74°
59°
5
77°
58°
6
74°
59°
7
73°
58°
8
74°
59°
9
74°
59°
10
71°
51°
11
71°
55°
12
72°
56°
13
72°
57°
14
71°
57°
15
72°
56°
16
71°
54°
17
68°
55°
18
72°
55°
19
68°
56°
20
70°
55°
21
71°
56°
22
70°
55°
23
71°
53°
24
65°
52°
25
61°
49°
26
63°
51°
27
67°
51°
28
68°
52°
29
68°
52°
30
67°
51°
1
68°
52°
2
68°
52°
3
66°
51°
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 77°, with overnight lows between 49° and 66°. The average high for September is 71° with an average low of 56°. 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.
