S
M
T
W
T
F
S
30
83°
75°
31
86°
75°
1
86°
75°
2
91°
75°
3
90°
77°
4
90°
77°
5
91°
77°
6
91°
75°
7
88°
75°
8
84°
73°
9
88°
75°
10
88°
77°
11
90°
75°
12
88°
73°
13
93°
77°
14
93°
79°
15
86°
77°
16
86°
70°
17
86°
68°
18
91°
70°
19
90°
72°
20
86°
73°
21
88°
75°
22
86°
75°
23
77°
70°
24
70°
64°
25
75°
55°
26
82°
54°
27
84°
54°
28
84°
61°
29
84°
63°
30
84°
68°
1
86°
66°
2
88°
70°
3
81°
75°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Charleston
Charleston's September 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. 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 Charleston. See also: October | November | December.
