Quilcene, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.1 °C (low) to 15.9 °C (high). Annual precipitation averages 931.9 Millimeters. Quilcene is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.8 °C | 8.3 °C | 136.4 mm |
| February | 1.7 °C | 9.7 °C | 98.3 mm |
| March | 2.9 °C | 12 °C | 115.57 mm |
| April | 4.7 °C | 15.2 °C | 66.04 mm |
| May | 7.6 °C | 18.7 °C | 40.13 mm |
| June | 10.1 °C | 20.8 °C | 42.93 mm |
| July | 11.7 °C | 24.4 °C | 20.83 mm |
| August | 11.7 °C | 24.9 °C | 19.05 mm |
| September | 9.6 °C | 22 °C | 29.97 mm |
| October | 6.4 °C | 15.9 °C | 69.34 mm |
| November | 3.4 °C | 10.8 °C | 132.84 mm |
| December | 1.7 °C | 7.9 °C | 160.53 mm |
| Annual | 6.1 °C | 15.9 °C | 931.93 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |