South Jacksonville Illinois Climate Data

Monthly Average Climate Data for South Jacksonville Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-7.5 °C1.8 °C54.36 mm
February-5.7 °C4.7 °C48.26 mm
March-0.6 °C11.1 °C73.91 mm
April5.2 °C18.1 °C106.68 mm
May11.7 °C23.6 °C123.7 mm
June16.8 °C28.4 °C125.73 mm
July18.7 °C30.2 °C103.12 mm
August17.3 °C29.4 °C84.84 mm
September12.6 °C26.4 °C88.14 mm
October6.3 °C19.5 °C76.96 mm
November0.4 °C11.4 °C75.69 mm
December-4.6 °C4.7 °C55.63 mm
Annual5.9 °C17.4 °C1017.02 mm

Climate Data for South Jacksonville Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 6a : -23.3°C to -20.6°C
Plant Hardiness Zone - 2012Zone 6a : -23.3°C to -20.6°C
Current Drought ConditionsNormal
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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