S
M
T
W
T
F
S
30
81°
54°
31
79°
61°
1
67°
59°
2
77°
59°
3
80°
62°
4
83°
63°
5
73°
60°
6
69°
54°
7
78°
54°
8
78°
53°
9
79°
57°
10
84°
65°
11
75°
52°
12
76°
50°
13
70°
59°
14
73°
49°
15
72°
46°
16
77°
50°
17
78°
62°
18
78°
60°
19
67°
50°
20
60°
53°
21
68°
47°
22
62°
45°
23
62°
47°
24
61°
48°
25
61°
50°
26
63°
49°
27
68°
47°
28
66°
46°
29
66°
48°
30
70°
48°
1
66°
46°
2
67°
45°
3
63°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Hopkinton
Hopkinton's September 2026 forecast shows daily high temperatures ranging from 60° to 70°, with overnight lows between 45° and 53°. The average high for September is 65° with an average low of 48°. 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 Hopkinton. See also: October | November | December.