S
M
T
W
T
F
S
26
49°
30°
27
51°
31°
28
52°
33°
29
60°
29°
30
66°
28°
1
71°
30°
2
72°
36°
3
73°
33°
4
65°
47°
5
59°
33°
6
67°
29°
7
68°
44°
8
70°
38°
9
70°
43°
10
73°
37°
11
74°
41°
12
76°
36°
13
65°
43°
14
58°
45°
15
60°
40°
16
48°
33°
17
53°
32°
18
58°
29°
19
58°
35°
20
59°
35°
21
62°
29°
22
68°
40°
23
74°
37°
24
77°
41°
25
83°
37°
26
N/A
27
82°
48°
28
87°
54°
29
83°
52°
30
62°
45°
31
60°
40°
1
65°
44°
2
74°
48°
3
75°
50°
4
79°
51°
5
80°
51°
6
77°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
May Weather in Lake McDonald
Lake McDonald's May 2026 forecast shows daily high temperatures ranging from 60° to 87°, with overnight lows between 40° and 54°. The average high for May is 75° with an average low of 48°. 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 Lake McDonald. See also: June | July | August.