S
M
T
W
T
F
S
30
73°
61°
31
70°
62°
1
72°
61°
2
81°
62°
3
80°
57°
4
77°
53°
5
74°
53°
6
73°
50°
7
75°
54°
8
73°
56°
9
70°
59°
10
68°
47°
11
66°
47°
12
68°
49°
13
69°
52°
14
69°
53°
15
71°
48°
16
72°
51°
17
71°
41°
18
63°
46°
19
67°
47°
20
70°
49°
21
71°
50°
22
70°
48°
23
69°
47°
24
64°
47°
25
68°
48°
26
67°
46°
27
66°
43°
28
57°
44°
29
57°
43°
30
56°
40°
1
55°
41°
2
56°
44°
3
60°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Peterborough
Peterborough's September 2026 forecast shows daily high temperatures ranging from 55° to 77°, with overnight lows between 40° and 59°. The average high for September is 67° 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 Peterborough. See also: October | November | December.
