S
M
T
W
T
F
S
26
55°
39°
27
68°
43°
28
64°
50°
29
54°
35°
30
49°
31°
1
46°
29°
2
52°
27°
3
68°
39°
4
80°
47°
5
60°
40°
6
53°
40°
7
54°
44°
8
63°
43°
9
66°
47°
10
63°
43°
11
59°
47°
12
61°
46°
13
65°
49°
14
62°
49°
15
66°
52°
16
67°
54°
17
71°
48°
18
64°
50°
19
69°
54°
20
69°
53°
21
66°
44°
22
63°
43°
23
63°
45°
24
65°
45°
25
64°
46°
26
64°
46°
27
65°
47°
28
66°
46°
29
66°
51°
30
68°
57°
31
74°
52°
1
68°
53°
2
72°
57°
3
74°
58°
4
76°
58°
5
77°
59°
6
78°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Round Lake
Round Lake's May 2026 forecast shows daily high temperatures ranging from 53° to 80°, with overnight lows between 40° and 60°. The average high for May is 67° with an average low of 49°. 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 Round Lake. See also: June | July | August.
