S
M
T
W
T
F
S
30
82°
61°
31
73°
63°
1
71°
60°
2
74°
58°
3
78°
64°
4
78°
64°
5
71°
59°
6
68°
56°
7
75°
60°
8
80°
62°
9
75°
69°
10
79°
63°
11
73°
60°
12
69°
58°
13
73°
60°
14
72°
62°
15
71°
61°
16
72°
57°
17
73°
56°
18
66°
57°
19
70°
60°
20
70°
59°
21
68°
58°
22
68°
59°
23
69°
59°
24
69°
58°
25
66°
58°
26
69°
57°
27
71°
59°
28
71°
56°
29
65°
55°
30
66°
56°
1
65°
54°
2
62°
55°
3
63°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Barnstable
Barnstable's September 2026 forecast shows daily high temperatures ranging from 62° to 80°, with overnight lows between 54° and 69°. The average high for September is 70° with an average low of 59°. 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 Barnstable. See also: October | November | December.
