S
M
T
W
T
F
S
30
75°
65°
31
76°
66°
1
81°
64°
2
77°
62°
3
79°
60°
4
76°
60°
5
75°
61°
6
78°
64°
7
80°
64°
8
80°
63°
9
79°
64°
10
78°
64°
11
77°
63°
12
80°
63°
13
80°
62°
14
79°
63°
15
79°
62°
16
80°
56°
17
77°
59°
18
71°
62°
19
76°
61°
20
77°
62°
21
78°
61°
22
77°
55°
23
75°
59°
24
75°
54°
25
Hist. Avg.
72°
56°
26
Hist. Avg.
72°
56°
27
Hist. Avg.
72°
55°
28
Hist. Avg.
71°
55°
29
Hist. Avg.
71°
55°
30
Hist. Avg.
70°
54°
1
Hist. Avg.
70°
54°
2
Hist. Avg.
70°
54°
3
Hist. Avg.
69°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Dartmouth
Dartmouth's September 2026 forecast shows daily high temperatures ranging from 71° to 81°, with overnight lows between 54° and 66°. The average high for September is 78° with an average low of 62°. 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 Dartmouth. See also: October | November | December.
