S
M
T
W
T
F
S
30
85°
63°
31
85°
63°
1
84°
60°
2
78°
55°
3
77°
55°
4
77°
56°
5
78°
54°
6
81°
59°
7
83°
61°
8
83°
60°
9
81°
60°
10
83°
61°
11
84°
60°
12
83°
61°
13
84°
62°
14
83°
52°
15
76°
51°
16
73°
51°
17
75°
52°
18
73°
50°
19
74°
49°
20
73°
49°
21
78°
51°
22
78°
55°
23
79°
48°
24
79°
47°
25
72°
46°
26
72°
48°
27
73°
53°
28
75°
53°
29
77°
45°
30
71°
46°
1
69°
52°
2
70°
51°
3
73°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Plainsboro Township
Plainsboro Township's September 2026 forecast shows daily high temperatures ranging from 69° to 85°, with overnight lows between 45° and 63°. The average high for September is 78° with an average low of 54°. 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 Plainsboro Township. See also: October | November | December.
