S
M
T
W
T
F
S
26
84°
57°
27
84°
63°
28
77°
64°
29
73°
61°
30
68°
52°
1
66°
46°
2
70°
43°
3
73°
39°
4
N/A
5
74°
61°
6
65°
50°
7
66°
45°
8
74°
51°
9
77°
56°
10
79°
59°
11
70°
46°
12
71°
47°
13
80°
58°
14
82°
60°
15
81°
62°
16
82°
63°
17
80°
63°
18
79°
57°
19
79°
61°
20
77°
61°
21
80°
56°
22
75°
54°
23
75°
53°
24
76°
54°
25
74°
55°
26
75°
54°
27
76°
54°
28
77°
56°
29
78°
59°
30
83°
63°
31
82°
64°
1
79°
64°
2
80°
62°
3
79°
60°
4
80°
64°
5
81°
65°
6
82°
66°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
May Weather in Walnut
Walnut's May 2026 forecast shows daily high temperatures ranging from 65° to 83°, with overnight lows between 45° and 66°. 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 Walnut. See also: June | July | August.