S
M
T
W
T
F
S
30
93°
64°
31
89°
64°
1
87°
68°
2
91°
69°
3
92°
68°
4
91°
68°
5
91°
67°
6
90°
66°
7
89°
66°
8
88°
65°
9
88°
63°
10
86°
65°
11
88°
65°
12
89°
67°
13
89°
66°
14
83°
60°
15
82°
58°
16
Hist. Avg.
87°
64°
17
Hist. Avg.
87°
64°
18
Hist. Avg.
87°
63°
19
Hist. Avg.
87°
63°
20
Hist. Avg.
86°
62°
21
Hist. Avg.
86°
62°
22
Hist. Avg.
86°
62°
23
Hist. Avg.
86°
61°
24
Hist. Avg.
85°
61°
25
Hist. Avg.
85°
61°
26
Hist. Avg.
85°
60°
27
Hist. Avg.
84°
60°
28
Hist. Avg.
84°
60°
29
Hist. Avg.
84°
59°
30
Hist. Avg.
83°
59°
1
Hist. Avg.
83°
58°
2
Hist. Avg.
83°
58°
3
Hist. Avg.
82°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Charleston
Charleston's September 2026 forecast shows daily high temperatures ranging from 82° to 93°, with overnight lows between 58° and 69°. The average high for September is 89° with an average low of 65°. 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.
