S
M
T
W
T
F
S
26
67°
55°
27
68°
52°
28
73°
46°
29
76°
48°
30
72°
56°
1
78°
54°
2
78°
58°
3
69°
58°
4
69°
57°
5
67°
54°
6
75°
50°
7
76°
52°
8
81°
59°
9
80°
59°
10
78°
57°
11
85°
54°
12
67°
61°
13
75°
57°
14
74°
61°
15
75°
61°
16
71°
61°
17
70°
56°
18
73°
58°
19
85°
51°
20
85°
52°
21
79°
56°
22
76°
60°
23
76°
61°
24
74°
62°
25
73°
59°
26
68°
61°
27
66°
55°
28
70°
55°
29
72°
54°
30
77°
54°
31
80°
58°
1
81°
60°
2
80°
58°
3
81°
59°
4
81°
62°
5
78°
61°
6
79°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Rancho San Diego
Rancho San Diego's May 2026 forecast shows daily high temperatures ranging from 66° to 81°, with overnight lows between 54° and 62°. The average high for May is 77° with an average low of 58°. 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 Rancho San Diego. See also: June | July | August.
