Kirkland, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.8 °C (low) to 15.9 °C (high). Annual precipitation averages 1011.4 Millimeters. Kirkland is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.1 °C | 8.3 °C | 136.14 mm |
| February | 2.1 °C | 9.8 °C | 96.52 mm |
| March | 3.4 °C | 12 °C | 106.68 mm |
| April | 5.3 °C | 14.8 °C | 81.79 mm |
| May | 8.3 °C | 18.7 °C | 53.85 mm |
| June | 10.7 °C | 21.1 °C | 47.24 mm |
| July | 12.6 °C | 24.7 °C | 20.07 mm |
| August | 12.7 °C | 25 °C | 25.4 mm |
| September | 10.6 °C | 21.7 °C | 42.67 mm |
| October | 7.2 °C | 15.8 °C | 100.33 mm |
| November | 4.1 °C | 10.8 °C | 151.89 mm |
| December | 1.9 °C | 7.8 °C | 148.84 mm |
| Annual | 6.8 °C | 15.9 °C | 1011.42 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 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 | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |