S
M
T
W
T
F
S
30
78°
63°
31
73°
61°
1
70°
62°
2
72°
63°
3
74°
66°
4
78°
63°
5
74°
61°
6
69°
59°
7
71°
63°
8
72°
62°
9
73°
61°
10
73°
64°
11
74°
63°
12
73°
63°
13
73°
61°
14
72°
57°
15
68°
61°
16
69°
60°
17
72°
60°
18
67°
59°
19
66°
60°
20
67°
60°
21
70°
61°
22
73°
61°
23
73°
60°
24
72°
60°
25
71°
59°
26
71°
59°
27
72°
60°
28
72°
59°
29
71°
58°
30
64°
56°
1
63°
56°
2
62°
57°
3
69°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Nantucket
Nantucket's September 2026 forecast shows daily high temperatures ranging from 62° to 78°, with overnight lows between 56° and 66°. The average high for September is 71° with an average low of 60°. 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 Nantucket. See also: October | November | December.
