S
M
T
W
T
F
S
30
87°
67°
31
87°
65°
1
86°
65°
2
81°
67°
3
87°
68°
4
88°
70°
5
90°
69°
6
89°
62°
7
80°
63°
8
81°
60°
9
82°
57°
10
81°
54°
11
78°
54°
12
77°
54°
13
76°
55°
14
77°
52°
15
82°
58°
16
79°
56°
17
80°
58°
18
81°
58°
19
80°
56°
20
79°
57°
21
81°
58°
22
81°
59°
23
80°
58°
24
81°
58°
25
80°
57°
26
79°
55°
27
80°
56°
28
80°
55°
29
79°
56°
30
79°
56°
1
78°
55°
2
78°
55°
3
77°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Amboy
Amboy's September 2026 forecast shows daily high temperatures ranging from 76° to 90°, with overnight lows between 52° and 70°. The average high for September is 81° with an average low of 58°. 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 Amboy. See also: October | November | December.