Bell Hill, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 5.5 °C (low) to 14.9 °C (high). Annual precipitation averages 593.1 Millimeters. Bell Hill is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.1 °C | 6.2 °C | 73.15 mm |
| February | 0.6 °C | 7.3 °C | 60.45 mm |
| March | 2 °C | 9.5 °C | 54.36 mm |
| April | 4.1 °C | 14.6 °C | 44.96 mm |
| May | 6.2 °C | 19 °C | 43.94 mm |
| June | 8.3 °C | 21.8 °C | 31.75 mm |
| July | 11.2 °C | 23.3 °C | 19.81 mm |
| August | 11.8 °C | 23.8 °C | 17.53 mm |
| September | 10.7 °C | 23 °C | 28.96 mm |
| October | 6.8 °C | 15.6 °C | 55.88 mm |
| November | 2.8 °C | 8.7 °C | 85.09 mm |
| December | 0.6 °C | 6.1 °C | 77.22 mm |
| Annual | 5.5 °C | 14.9 °C | 593.1 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |