Castle Rock Washington Climate Data

Monthly Average Climate Data for Castle Rock Washington

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January35.6 °F46.8 °F6.57 in.
February34.8 °F50.5 °F4.7 in.
March37.5 °F54.9 °F4.96 in.
April40.7 °F59.8 °F4.11 in.
May46.0 °F66.5 °F2.81 in.
June50.1 °F70.6 °F1.96 in.
July53.8 °F77.0 °F0.57 in.
August53.7 °F78.4 °F0.85 in.
September49.8 °F73.8 °F1.85 in.
October43.9 °F62.6 °F4.43 in.
November38.8 °F52.0 °F7.2 in.
December35.1 °F45.7 °F7.32 in.
Annual43.3 °F61.6 °F47.33 in.

Climate Data for Castle Rock Washington

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateMay 1 - May 10
Average Days With Frost50-75 Days
Plant Hardiness Zone - 2023Zone 8b : 15°F to 20°F
Plant Hardiness Zone - 2012Zone 8b : 15°F to 20°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationCsb - Warm-Summer Mediterranean Climate