S
M
T
W
T
F
S
30
75°
58°
31
76°
60°
1
81°
61°
2
81°
58°
3
80°
55°
4
80°
59°
5
79°
56°
6
79°
53°
7
73°
57°
8
71°
58°
9
73°
52°
10
78°
49°
11
72°
57°
12
75°
52°
13
78°
54°
14
74°
52°
15
70°
55°
16
Hist. Avg.
71°
53°
17
Hist. Avg.
70°
53°
18
Hist. Avg.
70°
52°
19
Hist. Avg.
70°
52°
20
Hist. Avg.
69°
52°
21
Hist. Avg.
69°
51°
22
Hist. Avg.
68°
51°
23
Hist. Avg.
68°
51°
24
Hist. Avg.
68°
50°
25
Hist. Avg.
67°
50°
26
Hist. Avg.
67°
49°
27
Hist. Avg.
66°
49°
28
Hist. Avg.
66°
49°
29
Hist. Avg.
65°
48°
30
Hist. Avg.
65°
48°
1
Hist. Avg.
65°
48°
2
Hist. Avg.
64°
47°
3
Hist. Avg.
64°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Westborough
Westborough's September 2026 forecast shows daily high temperatures ranging from 70° to 81°, with overnight lows between 49° and 61°. The average high for September is 76° with an average low of 56°. 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 Westborough. See also: October | November | December.
