S
M
T
W
T
F
S
30
92°
70°
31
93°
72°
1
96°
72°
2
97°
71°
3
96°
73°
4
94°
73°
5
95°
73°
6
92°
68°
7
80°
66°
8
94°
68°
9
82°
69°
10
82°
64°
11
81°
61°
12
76°
60°
13
70°
56°
14
82°
55°
15
76°
60°
16
72°
61°
17
81°
69°
18
91°
70°
19
89°
68°
20
71°
61°
21
65°
60°
22
62°
55°
23
70°
54°
24
68°
55°
25
63°
59°
26
72°
61°
27
70°
60°
28
76°
61°
29
77°
58°
30
71°
67°
1
70°
53°
2
67°
46°
3
72°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Princeton
Princeton's September 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. 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.
