S
M
T
W
T
F
S
30
71°
49°
31
70°
49°
1
69°
51°
2
70°
51°
3
70°
53°
4
69°
52°
5
70°
51°
6
68°
50°
7
68°
49°
8
69°
47°
9
68°
53°
10
69°
48°
11
66°
47°
12
69°
46°
13
70°
53°
14
73°
50°
15
69°
53°
16
74°
53°
17
73°
52°
18
73°
52°
19
72°
51°
20
73°
47°
21
66°
51°
22
67°
48°
23
66°
47°
24
65°
46°
25
61°
45°
26
68°
40°
27
68°
42°
28
59°
41°
29
57°
42°
30
57°
39°
1
Hist. Avg.
63°
44°
2
Hist. Avg.
63°
44°
3
Hist. Avg.
62°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Trenton
Trenton's September 2026 forecast shows daily high temperatures ranging from 57° to 74°, with overnight lows between 39° and 53°. The average high for September is 68° 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 Trenton. See also: October | November | December.
