Fairfield Illinois Climate Data

Monthly Average Climate Data for Fairfield Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-4.8 °C4.2 °C84.84 mm
February-3.3 °C6.9 °C69.85 mm
March1.4 °C12.6 °C101.6 mm
April7.1 °C19.3 °C123.7 mm
May12.9 °C24.6 °C124.97 mm
June17.8 °C29.4 °C122.43 mm
July19.4 °C31 °C99.31 mm
August18.1 °C30.5 °C85.85 mm
September13.7 °C27.3 °C79.25 mm
October7.4 °C20.9 °C90.93 mm
November1.7 °C12.8 °C99.06 mm
December-2.5 °C6.6 °C83.31 mm
Annual7.4 °C18.8 °C1165.1 mm

Climate Data for Fairfield Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateMay 1 - May 10
Average Days With Frost75-100 Days
Plant Hardiness Zone - 2023Zone 6b : -20.6°C to -17.8°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
2024 plantmaps.com