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°
69°
10
80°
62°
11
73°
57°
12
74°
62°
13
74°
66°
14
76°
60°
15
75°
69°
16
78°
62°
17
71°
61°
18
74°
60°
19
70°
56°
20
69°
58°
21
71°
59°
22
70°
57°
23
65°
59°
24
67°
59°
25
63°
53°
26
63°
55°
27
64°
57°
28
66°
58°
29
63°
57°
30
63°
57°
1
64°
56°
2
67°
57°
3
67°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in East Harwich
East Harwich's September 2026 forecast shows daily high temperatures ranging from 63° to 80°, with overnight lows between 53° 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 East Harwich. See also: October | November | December.
