Nehalem, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 44.1 °F (low) to 58.4 °F (high). Annual precipitation averages 82.6 Inches. Nehalem is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.7 °F | 50.2 °F | 11.99 in. |
| February | 38.1 °F | 51.3 °F | 8.2 in. |
| March | 39.0 °F | 53.2 °F | 9.5 in. |
| April | 41.1 °F | 56.0 °F | 6.98 in. |
| May | 45.4 °F | 60.0 °F | 4.15 in. |
| June | 49.3 °F | 63.2 °F | 3.52 in. |
| July | 52.2 °F | 66.7 °F | 1.01 in. |
| August | 52.3 °F | 68.0 °F | 1.92 in. |
| September | 49.4 °F | 67.2 °F | 2.95 in. |
| October | 45.1 °F | 61.0 °F | 7.2 in. |
| November | 41.0 °F | 54.2 °F | 12.51 in. |
| December | 38.1 °F | 49.4 °F | 12.64 in. |
| Annual | 44.1 °F | 58.4 °F | 82.57 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |