S
M
T
W
T
F
S
26
68°
48°
27
72°
52°
28
67°
53°
29
62°
45°
30
59°
38°
1
54°
39°
2
53°
35°
3
62°
37°
4
75°
49°
5
60°
46°
6
58°
43°
7
61°
35°
8
67°
49°
9
74°
52°
10
68°
47°
11
72°
41°
12
78°
38°
13
65°
46°
14
66°
40°
15
68°
44°
16
76°
60°
17
85°
63°
18
87°
66°
19
85°
66°
20
69°
56°
21
66°
49°
22
65°
55°
23
69°
57°
24
75°
57°
25
79°
57°
26
80°
65°
27
78°
62°
28
79°
55°
29
79°
53°
30
74°
50°
31
73°
53°
1
74°
54°
2
75°
55°
3
79°
58°
4
80°
60°
5
80°
61°
6
80°
62°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Castleton
Castleton's May 2026 forecast shows daily high temperatures ranging from 73° to 80°, with overnight lows between 50° and 65°. The average high for May is 78° with an average low of 57°. 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 Castleton. See also: June | July | August.
