S
M
T
W
T
F
S
30
76°
56°
31
79°
60°
1
80°
61°
2
80°
61°
3
79°
59°
4
76°
57°
5
75°
56°
6
74°
55°
7
75°
58°
8
78°
55°
9
74°
53°
10
74°
53°
11
80°
47°
12
71°
47°
13
73°
49°
14
72°
48°
15
71°
47°
16
72°
48°
17
71°
46°
18
73°
50°
19
71°
47°
20
72°
45°
21
69°
44°
22
69°
48°
23
72°
46°
24
76°
45°
25
75°
49°
26
75°
50°
27
74°
47°
28
67°
46°
29
74°
48°
30
74°
40°
1
67°
48°
2
72°
49°
3
73°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Holliston
Holliston's September 2026 forecast shows daily high temperatures ranging from 67° to 80°, with overnight lows between 40° and 61°. The average high for September is 74° with an average low of 50°. 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 Holliston. See also: October | November | December.
