Chemainus, British Columbia climate data is summarized below. Average annual temperatures range from 6.9 °C (low) to 13.5 °C (high). Annual precipitation averages 1597 Millimeters. Chemainus is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.61 °C | 5.87 °C | 210 mm |
| February | 2.55 °C | 7.55 °C | 144 mm |
| March | 3.17 °C | 9 °C | 160 mm |
| April | 5.04 °C | 12.3 °C | 79 mm |
| May | 8.6 °C | 16.49 °C | 66 mm |
| June | 11.15 °C | 18.95 °C | 47 mm |
| July | 13.73 °C | 22.52 °C | 31 mm |
| August | 13.75 °C | 22.51 °C | 41 mm |
| September | 10.95 °C | 18.95 °C | 95 mm |
| October | 7.21 °C | 13.23 °C | 237 mm |
| November | 3.68 °C | 8.75 °C | 274 mm |
| December | 1.36 °C | 5.63 °C | 213 mm |
| Annual | 6.9 °C | 13.5 °C | 1597 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |