S
M
T
W
T
F
S
26
61°
35°
27
61°
27°
28
63°
24°
29
66°
29°
30
60°
29°
1
55°
26°
2
62°
20°
3
68°
27°
4
67°
41°
5
64°
40°
6
57°
22°
7
64°
13°
8
74°
29°
9
76°
29°
10
73°
32°
11
79°
32°
12
82°
31°
13
83°
36°
14
80°
40°
15
79°
32°
16
81°
34°
17
73°
37°
18
64°
34°
19
70°
27°
20
70°
35°
21
73°
26°
22
70°
27°
23
69°
41°
24
73°
45°
25
70°
45°
26
60°
40°
27
66°
41°
28
71°
40°
29
71°
40°
30
69°
40°
31
67°
43°
1
70°
46°
2
69°
44°
3
69°
46°
4
70°
44°
5
76°
40°
6
74°
41°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in San Luis
San Luis's May 2026 forecast shows daily high temperatures ranging from 60° to 76°, with overnight lows between 40° and 46°. The average high for May is 70° with an average low of 42°. 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 San Luis. See also: June | July | August.