S
M
T
W
T
F
S
30
66°
57°
31
68°
52°
1
68°
51°
2
65°
55°
3
65°
51°
4
70°
50°
5
67°
52°
6
66°
54°
7
69°
55°
8
68°
56°
9
70°
54°
10
68°
54°
11
67°
56°
12
69°
55°
13
69°
55°
14
68°
56°
15
69°
54°
16
69°
53°
17
66°
55°
18
67°
54°
19
69°
49°
20
66°
48°
21
65°
49°
22
64°
48°
23
65°
53°
24
66°
54°
25
66°
55°
26
68°
54°
27
67°
54°
28
67°
53°
29
64°
52°
30
61°
48°
1
61°
46°
2
62°
45°
3
61°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Newhaven
Newhaven's September 2026 forecast shows daily high temperatures ranging from 61° to 70°, with overnight lows between 45° and 57°. The average high for September is 66° with an average low of 52°. 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 Newhaven. See also: October | November | December.
