S
M
T
W
T
F
S
26
69°
50°
27
82°
44°
28
76°
55°
29
66°
53°
30
58°
41°
1
66°
36°
2
55°
36°
3
63°
32°
4
76°
42°
5
77°
61°
6
62°
52°
7
64°
42°
8
70°
35°
9
71°
51°
10
77°
49°
11
69°
46°
12
79°
52°
13
72°
45°
14
62°
40°
15
71°
52°
16
86°
61°
17
88°
65°
18
90°
68°
19
89°
64°
20
77°
58°
21
81°
63°
22
80°
61°
23
82°
61°
24
83°
63°
25
80°
56°
26
81°
60°
27
81°
59°
28
80°
61°
29
82°
61°
30
82°
62°
31
80°
61°
1
77°
58°
2
77°
56°
3
82°
62°
4
82°
63°
5
76°
62°
6
80°
62°
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 62° to 90°, with overnight lows between 40° and 68°. The average high for May is 80° with an average low of 59°. 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.
