S
M
T
W
T
F
S
30
N/A
31
88°
70°
1
95°
73°
2
96°
74°
3
94°
70°
4
87°
68°
5
82°
62°
6
82°
64°
7
86°
63°
8
83°
63°
9
85°
66°
10
81°
60°
11
82°
59°
12
75°
58°
13
76°
57°
14
79°
63°
15
76°
63°
16
74°
62°
17
74°
57°
18
72°
53°
19
71°
54°
20
74°
59°
21
79°
61°
22
79°
61°
23
80°
60°
24
79°
60°
25
78°
58°
26
76°
58°
27
77°
59°
28
77°
59°
29
78°
58°
30
72°
53°
1
69°
50°
2
70°
55°
3
75°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Greencastle
Greencastle's September 2026 forecast shows daily high temperatures ranging from 69° to 96°, with overnight lows between 50° and 74°. The average high for September is 79° with an average low of 61°. 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 Greencastle. See also: October | November | December.
