S
M
T
W
T
F
S
26
74°
62°
27
76°
67°
28
77°
69°
29
78°
68°
30
77°
69°
1
77°
67°
2
75°
63°
3
77°
66°
4
76°
65°
5
78°
69°
6
76°
68°
7
77°
68°
8
75°
69°
9
78°
69°
10
77°
70°
11
81°
70°
12
82°
71°
13
82°
71°
14
81°
70°
15
81°
71°
16
80°
70°
17
77°
71°
18
77°
71°
19
78°
70°
20
78°
71°
21
76°
69°
22
77°
70°
23
80°
70°
24
78°
70°
25
81°
72°
26
83°
73°
27
84°
74°
28
85°
74°
29
84°
74°
30
84°
73°
31
83°
74°
1
82°
73°
2
83°
73°
3
83°
73°
4
84°
74°
5
83°
73°
6
82°
72°
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 74° to 85°, with overnight lows between 62° and 74°. The average high for May is 79° with an average low of 70°. 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.
