Monthly Historical AveragesO'Fallon, IL
Average Temperature
High
24°
Feels 25
Low
14°
Feels 13
Average Precipitation
13 Days
136.5mm
0cm
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Daily Historical Averages
S
M
T
W
T
F
S
ForecastThursday, May 28, 2026
Day
29°Feels 30
Wind
16 km/h E
Gust
24 km/h
Humidity
56%
P.O.P
30%
Night
18°Feels 18
Wind
15 km/h E
Gust
22 km/h
Humidity
93%
P.O.P
20%
Historical AveragesMay 28
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity