S
M
T
W
T
F
S
26
57°
40°
27
68°
46°
28
64°
51°
29
56°
39°
30
54°
36°
1
47°
36°
2
55°
45°
3
63°
49°
4
77°
48°
5
54°
42°
6
52°
41°
7
52°
40°
8
62°
48°
9
63°
47°
10
63°
50°
11
62°
49°
12
65°
50°
13
64°
49°
14
69°
50°
15
62°
47°
16
62°
46°
17
64°
55°
18
71°
54°
19
65°
55°
20
69°
55°
21
72°
54°
22
69°
56°
23
73°
51°
24
65°
50°
25
65°
52°
26
67°
58°
27
71°
56°
28
67°
54°
29
68°
51°
30
69°
50°
31
69°
50°
1
68°
56°
2
77°
55°
3
69°
53°
4
70°
51°
5
69°
52°
6
70°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Buffalo Grove
Buffalo Grove's May 2026 forecast shows daily high temperatures ranging from 47° to 77°, with overnight lows between 36° and 58°. The average high for May is 65° with an average low of 50°. 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 Buffalo Grove. See also: June | July | August.