North Yelm, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 5.7 °C (low) to 16.1 °C (high). Annual precipitation averages 1236.7 Millimeters. North Yelm 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 Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.4 °C | 8.2 °C | 182.37 mm |
| February | 1.2 °C | 9.8 °C | 120.4 mm |
| March | 2.4 °C | 12.2 °C | 137.41 mm |
| April | 4.1 °C | 15 °C | 97.03 mm |
| May | 7.1 °C | 18.8 °C | 58.17 mm |
| June | 9.6 °C | 21.4 °C | 45.97 mm |
| July | 11.6 °C | 25.2 °C | 17.78 mm |
| August | 11.6 °C | 25.6 °C | 25.4 mm |
| September | 9.2 °C | 22.4 °C | 43.43 mm |
| October | 5.9 °C | 16.1 °C | 124.21 mm |
| November | 3 °C | 10.8 °C | 202.95 mm |
| December | 1.2 °C | 7.7 °C | 181.61 mm |
| Annual | 5.7 °C | 16.1 °C | 1236.73 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |