S
M
T
W
T
F
S
30
66°
58°
31
70°
58°
1
71°
57°
2
72°
56°
3
68°
55°
4
70°
57°
5
69°
52°
6
70°
54°
7
67°
55°
8
69°
55°
9
67°
54°
10
65°
53°
11
64°
50°
12
64°
51°
13
65°
50°
14
64°
54°
15
64°
55°
16
68°
54°
17
67°
55°
18
68°
52°
19
69°
50°
20
63°
54°
21
64°
51°
22
64°
48°
23
63°
48°
24
62°
53°
25
63°
54°
26
65°
53°
27
66°
49°
28
65°
47°
29
63°
46°
30
61°
47°
1
62°
45°
2
61°
47°
3
63°
51°
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 72°, with overnight lows between 45° and 58°. 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.
