Roy, British Columbia climate data is summarized below. Average annual temperatures range from 4.6 °C (low) to 13.8 °C (high). Annual precipitation averages 1588 Millimeters. Roy is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.09 °C | 4.33 °C | 173 mm |
| February | -0.24 °C | 6.19 °C | 124 mm |
| March | 0.73 °C | 8.21 °C | 166 mm |
| April | 2.55 °C | 12.59 °C | 109 mm |
| May | 6.44 °C | 17.9 °C | 68 mm |
| June | 8.94 °C | 20.85 °C | 55 mm |
| July | 11.45 °C | 24.75 °C | 40 mm |
| August | 11.51 °C | 24.95 °C | 53 mm |
| September | 8.97 °C | 20.48 °C | 131 mm |
| October | 5.53 °C | 13.69 °C | 231 mm |
| November | 1.54 °C | 7.41 °C | 256 mm |
| December | -1.29 °C | 3.77 °C | 182 mm |
| Annual | 4.6 °C | 13.8 °C | 1588 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |