Cliffdell, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 33.8 °F (low) to 56.4 °F (high). Annual precipitation averages 36.4 Inches. 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 | 21.7 °F | 35.2 °F | 5.88 in. |
| February | 22.9 °F | 40.4 °F | 3.96 in. |
| March | 26.1 °F | 46.2 °F | 3.53 in. |
| April | 31.4 °F | 54.5 °F | 2.23 in. |
| May | 38.0 °F | 63.5 °F | 1.66 in. |
| June | 44.1 °F | 69.9 °F | 1.23 in. |
| July | 49.2 °F | 79.9 °F | 0.51 in. |
| August | 48.6 °F | 80.3 °F | 0.5 in. |
| September | 41.7 °F | 72.4 °F | 0.93 in. |
| October | 33.7 °F | 57.8 °F | 3.24 in. |
| November | 26.7 °F | 42.5 °F | 6.04 in. |
| December | 21.8 °F | 34.1 °F | 6.71 in. |
| Annual | 33.8 °F | 56.4 °F | 36.42 in. |
| 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 : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |