S
M
T
W
T
F
S
30
78°
60°
31
78°
66°
1
78°
63°
2
69°
61°
3
83°
67°
4
82°
68°
5
78°
62°
6
73°
59°
7
79°
58°
8
80°
64°
9
82°
69°
10
82°
63°
11
77°
55°
12
75°
61°
13
79°
63°
14
80°
61°
15
78°
62°
16
77°
58°
17
74°
57°
18
73°
58°
19
72°
59°
20
71°
55°
21
73°
59°
22
67°
58°
23
67°
58°
24
68°
57°
25
69°
54°
26
73°
54°
27
68°
50°
28
68°
54°
29
73°
56°
30
74°
57°
1
73°
56°
2
72°
56°
3
71°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Armonk
Armonk's September 2026 forecast shows daily high temperatures ranging from 67° to 82°, with overnight lows between 50° and 69°. The average high for September is 74° 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 Armonk. See also: October | November | December.
