Lewiston Idaho Climate Data

Monthly Average Climate Data for Lewiston Idaho

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-0.5 °C6.2 °C27.18 mm
February0.1 °C9.1 °C30.99 mm
March2.1 °C13.7 °C33.53 mm
April5.1 °C17.9 °C30.23 mm
May8.7 °C23.1 °C34.8 mm
June11.8 °C26.8 °C23.62 mm
July15.1 °C33.4 °C14.48 mm
August15 °C33.3 °C12.19 mm
September11.1 °C27.6 °C12.95 mm
October6.1 °C18.7 °C27.43 mm
November1.9 °C10.3 °C28.45 mm
December-0.9 °C5.4 °C22.35 mm
Annual6.3 °C18.8 °C298.2 mm

Climate Data for Lewiston Idaho

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost75-100 Days
Plant Hardiness Zone - 2023Zone 7b : -15°C to -12.2°C
Plant Hardiness Zone - 2012Zone 7b : -15°C to -12.2°C
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationBSk - Cold Semi-Arid Climate
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