Port Byron Illinois Climate Data

Monthly Average Climate Data for Port Byron Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-9.9 °C-1.1 °C39.12 mm
February-7.9 °C1.4 °C44.45 mm
March-2 °C8.6 °C63.75 mm
April4.2 °C16 °C94.23 mm
May10.7 °C22.3 °C120.9 mm
June16.3 °C27.4 °C125.73 mm
July18.3 °C29.2 °C113.79 mm
August17.1 °C28.1 °C102.62 mm
September12.6 °C24.8 °C88.65 mm
October5.9 °C17.6 °C71.63 mm
November-0.7 °C9.2 °C57.15 mm
December-6.5 °C2 °C52.32 mm
Annual4.8 °C15.5 °C974.34 mm

Climate Data for Port Byron Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
Average Days With Frost75-100 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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