S
M
T
W
T
F
S
26
66°
40°
27
69°
47°
28
64°
37°
29
65°
33°
30
55°
45°
1
66°
43°
2
73°
37°
3
86°
41°
4
86°
39°
5
58°
40°
6
47°
35°
7
77°
33°
8
77°
43°
9
89°
50°
10
69°
48°
11
81°
40°
12
87°
50°
13
84°
46°
14
96°
58°
15
91°
52°
16
96°
57°
17
89°
64°
18
76°
47°
19
69°
44°
20
66°
50°
21
61°
51°
22
72°
49°
23
76°
53°
24
80°
54°
25
83°
58°
26
86°
58°
27
80°
57°
28
80°
57°
29
82°
57°
30
85°
58°
31
83°
58°
1
85°
56°
2
79°
59°
3
76°
53°
4
78°
59°
5
83°
61°
6
87°
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 61° to 87°, with overnight lows between 44° and 62°. The average high for May is 78° with an average low of 55°. 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.
