S
M
T
W
T
F
S
26
65°
42°
27
69°
48°
28
61°
48°
29
57°
38°
30
56°
35°
1
49°
33°
2
56°
30°
3
68°
42°
4
79°
47°
5
56°
39°
6
54°
39°
7
58°
37°
8
61°
40°
9
62°
41°
10
61°
45°
11
63°
46°
12
66°
45°
13
68°
48°
14
68°
49°
15
70°
48°
16
71°
49°
17
70°
54°
18
69°
54°
19
73°
55°
20
71°
55°
21
69°
46°
22
65°
46°
23
65°
47°
24
67°
47°
25
66°
48°
26
66°
48°
27
67°
49°
28
68°
49°
29
69°
54°
30
70°
59°
31
75°
56°
1
71°
55°
2
75°
59°
3
76°
60°
4
79°
60°
5
79°
61°
6
80°
62°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in DeKalb
DeKalb's May 2026 forecast shows daily high temperatures ranging from 54° to 80°, with overnight lows between 37° and 62°. The average high for May is 68° 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 DeKalb. See also: June | July | August.
