Monmouth Illinois Climate Data

Monthly Average Climate Data for Monmouth Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-9.6 °C-0.4 °C43.94 mm
February-7.7 °C2.2 °C46.23 mm
March-1.7 °C9.6 °C64.26 mm
April4.1 °C16.7 °C97.03 mm
May10.8 °C22.7 °C127 mm
June16.1 °C27.6 °C120.4 mm
July17.9 °C29.3 °C100.58 mm
August16.7 °C28.4 °C94.74 mm
September12.1 °C25.3 °C97.54 mm
October5.6 °C18.3 °C71.88 mm
November-0.8 °C9.6 °C62.99 mm
December-6.3 °C2.6 °C50.29 mm
Annual4.8 °C16 °C976.88 mm

Climate Data for Monmouth Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateMay 1 - May 10
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 5b : -26.1°C to -23.3°C
Plant Hardiness Zone - 2012Zone 5b : -26.1°C to -23.3°C
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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