S
M
T
W
T
F
S
30
82°
54°
31
77°
53°
1
77°
54°
2
79°
57°
3
78°
59°
4
78°
58°
5
80°
58°
6
81°
57°
7
80°
53°
8
79°
51°
9
77°
52°
10
78°
53°
11
78°
52°
12
79°
52°
13
Hist. Avg.
73°
55°
14
Hist. Avg.
73°
55°
15
Hist. Avg.
73°
55°
16
Hist. Avg.
72°
54°
17
Hist. Avg.
72°
54°
18
Hist. Avg.
72°
54°
19
Hist. Avg.
72°
54°
20
Hist. Avg.
71°
53°
21
Hist. Avg.
71°
53°
22
Hist. Avg.
71°
53°
23
Hist. Avg.
70°
52°
24
Hist. Avg.
70°
52°
25
Hist. Avg.
70°
52°
26
Hist. Avg.
69°
51°
27
Hist. Avg.
69°
51°
28
Hist. Avg.
69°
51°
29
Hist. Avg.
68°
50°
30
Hist. Avg.
68°
50°
1
Hist. Avg.
68°
50°
2
Hist. Avg.
67°
49°
3
Hist. Avg.
67°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Princeton
Princeton's September 2026 forecast shows daily high temperatures ranging from 77° to 82°, with overnight lows between 51° and 59°. The average high for September is 79° with an average low of 55°. 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 Princeton. See also: October | November | December.
