S
M
T
W
T
F
S
30
83°
59°
31
84°
60°
1
82°
55°
2
81°
54°
3
81°
55°
4
79°
57°
5
77°
52°
6
75°
58°
7
79°
58°
8
82°
60°
9
83°
58°
10
74°
50°
11
72°
51°
12
79°
54°
13
80°
58°
14
81°
57°
15
80°
55°
16
75°
49°
17
72°
50°
18
76°
53°
19
79°
54°
20
Hist. Avg.
76°
49°
21
Hist. Avg.
76°
49°
22
Hist. Avg.
76°
49°
23
Hist. Avg.
76°
48°
24
Hist. Avg.
75°
48°
25
Hist. Avg.
75°
48°
26
Hist. Avg.
74°
48°
27
Hist. Avg.
74°
47°
28
Hist. Avg.
74°
47°
29
Hist. Avg.
73°
47°
30
Hist. Avg.
73°
47°
1
Hist. Avg.
72°
46°
2
Hist. Avg.
72°
46°
3
Hist. Avg.
71°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in West Haven-Sylvan
West Haven-Sylvan's September 2026 forecast shows daily high temperatures ranging from 72° to 84°, with overnight lows between 49° and 60°. The average high for September is 79° with an average low of 55°. 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 West Haven-Sylvan. See also: October | November | December.
