Ontario California Climate Data

Monthly Average Climate Data for Ontario California

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January6.6 °C19.6 °C83.82 mm
February7 °C19.8 °C98.3 mm
March8.3 °C21.5 °C59.18 mm
April9.7 °C23.6 °C17.53 mm
May12 °C25.7 °C9.65 mm
June14.2 °C29.3 °C2.54 mm
July16.8 °C32.9 °C1.27 mm
August17.2 °C33.9 °C0.51 mm
September16.2 °C32.3 °C2.79 mm
October12.9 °C27.7 °C15.75 mm
November8.8 °C23.3 °C20.57 mm
December6.2 °C19.1 °C57.91 mm
Annual11.3 °C25.7 °C369.82 mm

Climate Data for Ontario California

Average First Frost DateDec. 21 - Dec. 31
Average Last Frost DateFeb. 11 - Feb. 20
Average Days With Frost5-10 Days
Plant Hardiness Zone - 2023Zone 10a : -1.1°C to 1.7°C
Plant Hardiness Zone - 2012Zone 10a : -1.1°C to 1.7°C
Current Drought ConditionsNormal
Köppen Climate ClassificationCsa - Hot-Summer Mediterranean Climate
2024 plantmaps.com