S
M
T
W
T
F
S
30
92°
71°
31
92°
65°
1
88°
65°
2
87°
66°
3
88°
66°
4
92°
68°
5
92°
69°
6
91°
69°
7
88°
65°
8
87°
63°
9
86°
62°
10
85°
62°
11
86°
61°
12
85°
61°
13
84°
62°
14
84°
61°
15
85°
62°
16
85°
62°
17
84°
64°
18
87°
66°
19
88°
66°
20
87°
62°
21
88°
60°
22
Hist. Avg.
85°
61°
23
Hist. Avg.
84°
61°
24
Hist. Avg.
84°
61°
25
Hist. Avg.
84°
60°
26
Hist. Avg.
84°
60°
27
Hist. Avg.
83°
60°
28
Hist. Avg.
83°
59°
29
Hist. Avg.
82°
59°
30
Hist. Avg.
82°
58°
1
Hist. Avg.
82°
58°
2
Hist. Avg.
81°
58°
3
Hist. Avg.
81°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in New Haven
New Haven's September 2026 forecast shows daily high temperatures ranging from 84° to 92°, with overnight lows between 60° and 71°. The average high for September is 87° with an average low of 64°. 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 New Haven. See also: October | November | December.
