S
M
T
W
T
F
S
26
61°
50°
27
68°
46°
28
70°
37°
29
72°
52°
30
72°
50°
1
63°
43°
2
54°
45°
3
63°
37°
4
77°
43°
5
79°
54°
6
77°
59°
7
66°
52°
8
70°
46°
9
73°
46°
10
82°
54°
11
63°
41°
12
72°
36°
13
77°
41°
14
68°
50°
15
73°
45°
16
84°
52°
17
91°
63°
18
91°
66°
19
91°
68°
20
92°
65°
21
88°
62°
22
76°
62°
23
78°
65°
24
79°
66°
25
80°
65°
26
81°
63°
27
80°
61°
28
81°
60°
29
77°
57°
30
80°
62°
31
82°
61°
1
81°
60°
2
80°
59°
3
79°
59°
4
82°
63°
5
83°
63°
6
85°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Castalia
Castalia's May 2026 forecast shows daily high temperatures ranging from 76° to 92°, with overnight lows between 57° and 66°. The average high for May is 81° with an average low of 62°. 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 Castalia. See also: June | July | August.
