S
M
T
W
T
F
S
26
65°
31°
27
72°
33°
28
73°
38°
29
69°
39°
30
51°
40°
1
51°
33°
2
46°
31°
3
49°
37°
4
58°
43°
5
65°
44°
6
52°
38°
7
54°
36°
8
48°
34°
9
50°
39°
10
54°
43°
11
57°
39°
12
58°
41°
13
57°
40°
14
55°
40°
15
59°
40°
16
60°
37°
17
59°
37°
18
61°
43°
19
64°
46°
20
70°
47°
21
71°
43°
22
64°
39°
23
59°
44°
24
61°
42°
25
62°
41°
26
63°
40°
27
64°
43°
28
63°
47°
29
65°
49°
30
70°
46°
31
70°
41°
1
64°
41°
2
64°
42°
3
65°
42°
4
64°
44°
5
65°
43°
6
66°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Castlebar
Castlebar's May 2026 forecast shows daily high temperatures ranging from 46° to 71°, with overnight lows between 31° and 49°. The average high for May is 60° with an average low of 41°. 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 Castlebar. See also: June | July | August.
