Metaline, Washington has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 34.9 °F (low) to 57.3 °F (high). Annual precipitation averages 29.3 Inches. Metaline is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 21.6 °F | 32.3 °F | 3.05 in. |
| February | 23.0 °F | 39.1 °F | 2.16 in. |
| March | 27.1 °F | 47.8 °F | 2.56 in. |
| April | 32.8 °F | 57.7 °F | 2.36 in. |
| May | 40.6 °F | 67.5 °F | 2.67 in. |
| June | 46.5 °F | 73.2 °F | 3.24 in. |
| July | 50.6 °F | 83.5 °F | 1.4 in. |
| August | 49.6 °F | 84.2 °F | 0.9 in. |
| September | 42.4 °F | 73.2 °F | 1.25 in. |
| October | 34.8 °F | 56.2 °F | 2.56 in. |
| November | 27.8 °F | 40.5 °F | 3.71 in. |
| December | 21.6 °F | 32.2 °F | 3.45 in. |
| Annual | 34.9 °F | 57.3 °F | 29.31 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |