S
M
T
W
T
F
S
26
65°
37°
27
70°
39°
28
68°
42°
29
64°
47°
30
54°
40°
1
53°
37°
2
46°
30°
3
48°
38°
4
60°
50°
5
67°
51°
6
53°
42°
7
50°
37°
8
48°
34°
9
50°
41°
10
55°
45°
11
55°
41°
12
56°
43°
13
53°
44°
14
57°
43°
15
61°
41°
16
62°
44°
17
61°
42°
18
62°
51°
19
66°
51°
20
68°
50°
21
70°
52°
22
67°
49°
23
62°
50°
24
67°
46°
25
62°
44°
26
64°
46°
27
64°
52°
28
63°
53°
29
69°
52°
30
66°
50°
31
67°
45°
1
64°
45°
2
64°
46°
3
65°
46°
4
64°
47°
5
64°
47°
6
65°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Decatur
Decatur's May 2026 forecast shows daily high temperatures ranging from 46° to 70°, with overnight lows between 30° and 53°. The average high for May is 60° with an average low of 45°. 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 Decatur. See also: June | July | August.
