S
M
T
W
T
F
S
30
86°
65°
31
83°
58°
1
77°
57°
2
76°
57°
3
76°
58°
4
81°
64°
5
83°
65°
6
81°
65°
7
80°
64°
8
81°
62°
9
82°
62°
10
82°
63°
11
84°
64°
12
83°
63°
13
82°
63°
14
82°
57°
15
83°
51°
16
73°
50°
17
72°
50°
18
72°
51°
19
73°
57°
20
73°
59°
21
71°
56°
22
72°
54°
23
76°
58°
24
79°
57°
25
80°
57°
26
79°
58°
27
79°
55°
28
78°
46°
29
75°
47°
30
66°
50°
1
65°
49°
2
67°
54°
3
66°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mount Joy
Mount Joy's September 2026 forecast shows daily high temperatures ranging from 65° to 86°, with overnight lows between 46° and 65°. The average high for September is 77° with an average low of 57°. 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 Mount Joy. See also: October | November | December.
