Rio Illinois Climate Data

Monthly Average Climate Data for Rio Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January14.1 °F30.6 °F1.66 in.
February17.5 °F35.1 °F1.87 in.
March28.0 °F48.3 °F2.41 in.
April38.7 °F61.5 °F3.81 in.
May50.8 °F72.2 °F4.98 in.
June60.6 °F81.1 °F4.77 in.
July64.0 °F84.1 °F3.99 in.
August61.8 °F82.5 °F3.71 in.
September53.5 °F76.7 °F3.78 in.
October41.8 °F64.0 °F2.87 in.
November30.1 °F48.7 °F2.37 in.
December20.1 °F36.0 °F1.99 in.
Annual40.1 °F60.1 °F38.21 in.

Climate Data for Rio Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 5b : -15°F to -10°F
Plant Hardiness Zone - 2012Zone 5b : -15°F to -10°F
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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