Burien, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.7 °C (low) to 15.7 °C (high). Annual precipitation averages 1097.3 Millimeters. Burien is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.2 °C | 8.1 °C | 154.18 mm |
| February | 2.1 °C | 9.4 °C | 109.22 mm |
| March | 3.3 °C | 11.7 °C | 121.16 mm |
| April | 5.2 °C | 14.7 °C | 89.92 mm |
| May | 8.1 °C | 18.6 °C | 53.59 mm |
| June | 10.5 °C | 21 °C | 42.16 mm |
| July | 12.5 °C | 24.7 °C | 19.05 mm |
| August | 12.7 °C | 24.9 °C | 23.37 mm |
| September | 10.7 °C | 21.6 °C | 40.64 mm |
| October | 7.2 °C | 15.6 °C | 114.81 mm |
| November | 3.9 °C | 10.5 °C | 165.61 mm |
| December | 1.9 °C | 7.6 °C | 163.58 mm |
| Annual | 6.7 °C | 15.7 °C | 1097.29 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |