S
M
T
W
T
F
S
30
75°
63°
31
77°
63°
1
80°
62°
2
80°
63°
3
79°
62°
4
75°
60°
5
74°
61°
6
80°
59°
7
73°
58°
8
77°
60°
9
79°
61°
10
80°
60°
11
80°
52°
12
77°
59°
13
73°
58°
14
74°
60°
15
75°
60°
16
77°
59°
17
78°
59°
18
77°
58°
19
75°
59°
20
77°
51°
21
76°
48°
22
68°
56°
23
68°
55°
24
71°
56°
25
72°
57°
26
74°
50°
27
75°
47°
28
66°
46°
29
65°
52°
30
65°
49°
1
64°
46°
2
64°
50°
3
65°
53°
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 64° to 80°, with overnight lows between 46° and 63°. The average high for September is 74° 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.
