S
M
T
W
T
F
S
30
74°
52°
31
72°
52°
1
73°
56°
2
74°
60°
3
74°
60°
4
81°
61°
5
80°
59°
6
79°
52°
7
76°
51°
8
74°
51°
9
73°
50°
10
71°
51°
11
71°
51°
12
70°
52°
13
75°
54°
14
76°
56°
15
75°
56°
16
70°
52°
17
71°
53°
18
72°
55°
19
74°
47°
20
71°
50°
21
71°
47°
22
74°
45°
23
68°
45°
24
68°
46°
25
67°
51°
26
67°
44°
27
68°
50°
28
66°
49°
29
65°
42°
30
66°
44°
1
65°
49°
2
71°
45°
3
69°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Southbury
Southbury's September 2026 forecast shows daily high temperatures ranging from 65° to 81°, with overnight lows between 42° and 61°. The average high for September is 72° with an average low of 51°. 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 Southbury. See also: October | November | December.
