Cliffdell, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 1 °C (low) to 13.6 °C (high). Annual precipitation averages 925.1 Millimeters. Cliffdell is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.7 °C | 1.8 °C | 149.35 mm |
| February | -5.1 °C | 4.7 °C | 100.58 mm |
| March | -3.3 °C | 7.9 °C | 89.66 mm |
| April | -0.3 °C | 12.5 °C | 56.64 mm |
| May | 3.3 °C | 17.5 °C | 42.16 mm |
| June | 6.7 °C | 21.1 °C | 31.24 mm |
| July | 9.6 °C | 26.6 °C | 12.95 mm |
| August | 9.2 °C | 26.8 °C | 12.7 mm |
| September | 5.4 °C | 22.4 °C | 23.62 mm |
| October | 0.9 °C | 14.3 °C | 82.3 mm |
| November | -2.9 °C | 5.8 °C | 153.42 mm |
| December | -5.7 °C | 1.2 °C | 170.43 mm |
| Annual | 1 °C | 13.6 °C | 925.05 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |