Republic, Washington has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.8 °F (low) to 56.3 °F (high). Annual precipitation averages 18.2 Inches. Republic is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.7 °F | 30.6 °F | 1.63 in. |
| February | 18.9 °F | 37.6 °F | 1.26 in. |
| March | 25.1 °F | 47.1 °F | 1.57 in. |
| April | 30.5 °F | 57.1 °F | 1.39 in. |
| May | 38.3 °F | 66.8 °F | 2.02 in. |
| June | 43.9 °F | 72.6 °F | 2.2 in. |
| July | 48.0 °F | 82.4 °F | 1.24 in. |
| August | 46.8 °F | 82.9 °F | 0.67 in. |
| September | 39.5 °F | 73.1 °F | 0.79 in. |
| October | 31.2 °F | 56.5 °F | 1.22 in. |
| November | 24.4 °F | 39.3 °F | 1.94 in. |
| December | 17.7 °F | 29.8 °F | 2.29 in. |
| Annual | 31.8 °F | 56.3 °F | 18.22 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |