S
M
T
W
T
F
S
30
84°
61°
31
80°
69°
1
92°
72°
2
78°
69°
3
86°
69°
4
87°
69°
5
81°
63°
6
79°
60°
7
78°
56°
8
83°
54°
9
88°
62°
10
86°
70°
11
81°
63°
12
80°
62°
13
85°
68°
14
76°
55°
15
75°
48°
16
85°
58°
17
83°
69°
18
81°
63°
19
73°
62°
20
77°
65°
21
70°
60°
22
59°
52°
23
66°
49°
24
68°
47°
25
73°
54°
26
72°
55°
27
69°
52°
28
71°
54°
29
72°
54°
30
70°
55°
1
72°
54°
2
67°
48°
3
63°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Harrisburg
Harrisburg's September 2026 forecast shows daily high temperatures ranging from 59° to 73°, with overnight lows between 47° and 55°. The average high for September is 69° with an average low of 52°. 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 Harrisburg. See also: October | November | December.
