Monthly Historical AveragesVandalia, IL
Average Temperature
High
24°
Feels 24
Low
13°
Feels 12
Average Precipitation
13 Days
115.9mm
0cm
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Daily Historical Averages
S
M
T
W
T
F
S
ForecastSunday, May 31, 2026
Day
27°Feels 27
Wind
12 km/h E
Gust
18 km/h
Humidity
51%
P.O.P
40%
Rain
<1 mm
Night
17°Feels 17
Wind
9 km/h E
Gust
14 km/h
Humidity
95%
P.O.P
80%
Rain
~5 mm
Historical AveragesMay 31
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity