Rock Island Washington Climate Data

Monthly Average Climate Data for Rock Island Washington

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-3.4 °C2.5 °C35.05 mm
February-2.1 °C6.9 °C22.61 mm
March0.8 °C12.8 °C22.35 mm
April4.4 °C18.1 °C16.76 mm
May8.9 °C23.6 °C19.56 mm
June12.4 °C27.1 °C14.73 mm
July15.9 °C32.3 °C7.11 mm
August15.4 °C31.9 °C5.08 mm
September10.8 °C26.8 °C6.86 mm
October4.8 °C17.9 °C18.54 mm
November-0.1 °C8.6 °C22.61 mm
December-3.2 °C2.5 °C37.59 mm
Annual5.4 °C17.6 °C228.85 mm

Climate Data for Rock Island Washington

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateApr. 11 - Apr. 20
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 7b : -15°C to -12.2°C
Plant Hardiness Zone - 2012Zone 7a : -17.8°C to -15°C
Current Drought ConditionsNormal
Köppen Climate ClassificationBSk - Cold Semi-Arid Climate
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