S
M
T
W
T
F
S
26
64°
32°
27
71°
37°
28
71°
46°
29
69°
43°
30
53°
42°
1
52°
36°
2
47°
36°
3
47°
33°
4
63°
33°
5
77°
52°
6
52°
42°
7
51°
36°
8
48°
36°
9
59°
32°
10
62°
43°
11
51°
37°
12
51°
36°
13
48°
35°
14
54°
48°
15
64°
50°
16
74°
51°
17
72°
52°
18
80°
63°
19
81°
66°
20
70°
36°
21
53°
37°
22
62°
40°
23
58°
42°
24
57°
46°
25
63°
48°
26
66°
51°
27
68°
50°
28
70°
49°
29
68°
50°
30
68°
49°
31
69°
46°
1
66°
49°
2
65°
50°
3
63°
49°
4
62°
51°
5
65°
52°
6
71°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Charleston
Charleston's May 2026 forecast shows daily high temperatures ranging from 53° to 81°, with overnight lows between 36° and 66°. The average high for May is 66° with an average low of 49°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Charleston. See also: June | July | August.
