S
M
T
W
T
F
S
26
35°
14°
27
35°
18°
28
39°
11°
29
37°
21°
30
42°
15°
1
52°
18°
2
57°
21°
3
58°
26°
4
56°
26°
5
42°
22°
6
52°
16°
7
54°
29°
8
58°
27°
9
54°
28°
10
63°
25°
11
69°
29°
12
69°
32°
13
68°
30°
14
53°
28°
15
54°
24°
16
50°
30°
17
38°
23°
18
42°
25°
19
46°
23°
20
48°
25°
21
56°
26°
22
51°
28°
23
52°
30°
24
54°
28°
25
64°
36°
26
52°
31°
27
48°
27°
28
46°
25°
29
48°
25°
30
51°
30°
31
53°
35°
1
48°
31°
2
50°
32°
3
52°
30°
4
57°
35°
5
61°
36°
6
61°
36°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Yellowstone Lake
Yellowstone Lake's May 2026 forecast shows daily high temperatures ranging from 38° to 69°, with overnight lows between 23° and 36°. The average high for May is 53° with an average low of 29°. 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 Yellowstone Lake. See also: June | July | August.