Centralia, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 42.1 °F (low) to 61.8 °F (high). Annual precipitation averages 45.3 Inches. Centralia is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 34.9 °F | 46.9 °F | 6.49 in. |
| February | 34.4 °F | 50.3 °F | 4.59 in. |
| March | 36.3 °F | 54.8 °F | 5.0 in. |
| April | 39.0 °F | 60.1 °F | 3.45 in. |
| May | 44.5 °F | 67.0 °F | 2.19 in. |
| June | 48.7 °F | 71.6 °F | 1.64 in. |
| July | 52.2 °F | 78.3 °F | 0.52 in. |
| August | 52.2 °F | 79.4 °F | 0.77 in. |
| September | 48.1 °F | 73.8 °F | 1.61 in. |
| October | 42.5 °F | 62.1 °F | 4.21 in. |
| November | 37.5 °F | 51.8 °F | 7.55 in. |
| December | 34.4 °F | 45.8 °F | 7.28 in. |
| Annual | 42.1 °F | 61.8 °F | 45.3 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |