S
M
T
W
T
F
S
30
81°
63°
31
71°
63°
1
68°
62°
2
73°
63°
3
76°
61°
4
79°
63°
5
72°
58°
6
68°
55°
7
75°
57°
8
76°
61°
9
76°
61°
10
80°
69°
11
74°
59°
12
72°
54°
13
70°
62°
14
71°
60°
15
65°
51°
16
71°
64°
17
76°
68°
18
75°
55°
19
65°
54°
20
64°
59°
21
64°
57°
22
65°
56°
23
66°
58°
24
68°
57°
25
65°
56°
26
67°
57°
27
68°
55°
28
66°
54°
29
65°
51°
30
62°
55°
1
61°
54°
2
68°
55°
3
61°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Wellfleet
Wellfleet's September 2026 forecast shows daily high temperatures ranging from 61° to 76°, with overnight lows between 51° and 68°. The average high for September is 67° with an average low of 57°. 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 Wellfleet. See also: October | November | December.