S
M
T
W
T
F
S
30
87°
75°
31
86°
73°
1
86°
75°
2
87°
74°
3
85°
72°
4
83°
74°
5
83°
73°
6
86°
76°
7
86°
77°
8
85°
76°
9
85°
76°
10
86°
75°
11
86°
76°
12
85°
76°
13
85°
75°
14
84°
75°
15
84°
74°
16
83°
74°
17
84°
71°
18
84°
73°
19
82°
72°
20
83°
73°
21
84°
74°
22
80°
73°
23
83°
72°
24
82°
73°
25
82°
72°
26
82°
72°
27
79°
72°
28
82°
72°
29
83°
72°
30
Hist. Avg.
80°
69°
1
Hist. Avg.
80°
69°
2
Hist. Avg.
79°
68°
3
Hist. Avg.
79°
68°
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 79° to 87°, with overnight lows between 71° and 77°. The average high for September is 84° with an average low of 74°. 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.
