S
M
T
W
T
F
S
26
85°
84°
27
86°
84°
28
86°
83°
29
88°
83°
30
87°
84°
1
86°
84°
2
86°
82°
3
86°
84°
4
86°
84°
5
87°
83°
6
86°
84°
7
86°
83°
8
87°
82°
9
86°
82°
10
85°
81°
11
86°
82°
12
86°
81°
13
87°
82°
14
87°
81°
15
89°
82°
16
88°
81°
17
89°
80°
18
88°
81°
19
89°
80°
20
88°
81°
21
89°
82°
22
88°
81°
23
88°
81°
24
89°
82°
25
88°
81°
26
88°
81°
27
89°
80°
28
89°
81°
29
90°
82°
30
91°
81°
31
90°
82°
1
90°
82°
2
91°
81°
3
89°
81°
4
90°
82°
5
91°
81°
6
89°
82°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Ko Samui
Ko Samui's May 2026 forecast shows daily high temperatures ranging from 85° to 91°, with overnight lows between 80° and 84°. The average high for May is 88° with an average low of 82°. 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 Ko Samui. See also: June | July | August.
