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Current
Hourly
7 Days
14 Days
Weekend
Monthly
Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Decatur, IL
Content continues below
May
Average Temperature
High
24°
Feels 24
Low
13°
Feels 12
Average Precipitation
13 Days
Rain amount
102.1mm
Snow amount
0cm
Content continues below
Daily Historical Averages
May 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
29°
18
26°
19
27°
20
18°
21
21°
22
23°
23
25°
24
27°
25
27°
26
28°
27
27°
28
28°
29
28°
30
27°
31
28°
Forecast
Sunday, May 17, 2026
Day
29°
Feels 31
Wind
37 km/h S
Gust
55 km/h
Humidity
58%
P.O.P
30%
Night
20°
Feels 20
Wind
31 km/h S
Gust
46 km/h
Humidity
76%
P.O.P
20%
Historical Averages
May 17
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.