S
M
T
W
T
F
S
26
78°
44°
27
65°
58°
28
62°
53°
29
61°
44°
30
62°
38°
1
57°
43°
2
57°
40°
3
69°
51°
4
72°
55°
5
59°
42°
6
60°
44°
7
59°
41°
8
64°
50°
9
68°
49°
10
68°
52°
11
71°
52°
12
72°
54°
13
70°
50°
14
73°
52°
15
69°
56°
16
68°
54°
17
70°
59°
18
76°
60°
19
75°
60°
20
76°
61°
21
76°
61°
22
75°
60°
23
74°
54°
24
70°
54°
25
72°
61°
26
75°
61°
27
72°
56°
28
71°
55°
29
72°
53°
30
73°
60°
31
78°
58°
1
74°
62°
2
81°
64°
3
80°
59°
4
74°
56°
5
74°
56°
6
75°
57°
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 57° to 81°, with overnight lows between 40° and 64°. The average high for May is 71° with an average low of 54°. 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.
