S
M
T
W
T
F
S
30
79°
57°
31
82°
61°
1
86°
54°
2
83°
55°
3
78°
54°
4
79°
55°
5
80°
61°
6
83°
60°
7
86°
59°
8
79°
60°
9
77°
60°
10
81°
59°
11
82°
58°
12
81°
58°
13
79°
56°
14
76°
51°
15
76°
51°
16
75°
50°
17
75°
51°
18
76°
56°
19
78°
56°
20
79°
57°
21
80°
53°
22
76°
49°
23
73°
54°
24
72°
56°
25
78°
49°
26
72°
53°
27
76°
53°
28
77°
52°
29
73°
53°
30
Hist. Avg.
73°
51°
1
Hist. Avg.
72°
50°
2
Hist. Avg.
72°
50°
3
Hist. Avg.
72°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Monmouth Junction
Monmouth Junction's September 2026 forecast shows daily high temperatures ranging from 72° to 86°, with overnight lows between 49° and 61°. The average high for September is 78° 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 Monmouth Junction. See also: October | November | December.
