Rock Island Washington Climate Data

Monthly Average Climate Data for Rock Island Washington

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January25.8 °F36.5 °F1.38 in.
February28.3 °F44.5 °F0.89 in.
March33.5 °F55.0 °F0.88 in.
April39.9 °F64.6 °F0.66 in.
May48.1 °F74.4 °F0.77 in.
June54.4 °F80.8 °F0.58 in.
July60.7 °F90.2 °F0.28 in.
August59.8 °F89.5 °F0.2 in.
September51.4 °F80.2 °F0.27 in.
October40.6 °F64.3 °F0.73 in.
November31.9 °F47.4 °F0.89 in.
December26.2 °F36.5 °F1.48 in.
Annual41.7 °F63.7 °F9.01 in.

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 : 5°F to 10°F
Plant Hardiness Zone - 2012Zone 7a : 0°F to 5°F
Current Drought ConditionsNormal
Köppen Climate ClassificationBSk - Cold Semi-Arid Climate