Longview, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 43.7 °F (low) to 61.4 °F (high). Annual precipitation averages 46.2 Inches. Longview 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 | 35.8 °F | 46.7 °F | 6.5 in. |
| February | 35.1 °F | 50.3 °F | 4.55 in. |
| March | 37.9 °F | 54.7 °F | 4.8 in. |
| April | 41.0 °F | 59.5 °F | 4.01 in. |
| May | 46.4 °F | 66.1 °F | 2.75 in. |
| June | 50.5 °F | 70.3 °F | 1.99 in. |
| July | 54.2 °F | 76.7 °F | 0.54 in. |
| August | 54.2 °F | 78.0 °F | 0.8 in. |
| September | 50.2 °F | 73.5 °F | 1.87 in. |
| October | 44.2 °F | 62.4 °F | 4.37 in. |
| November | 39.1 °F | 52.2 °F | 6.96 in. |
| December | 35.4 °F | 45.8 °F | 7.06 in. |
| Annual | 43.7 °F | 61.4 °F | 46.2 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 50-75 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 | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |