Waterdown, Ontario climate data is summarized below. Average annual temperatures range from 4.6 °C (low) to 13.3 °C (high). Annual precipitation averages 947 Millimeters. Waterdown is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.57 °C | -0.78 °C | 26 mm |
| February | -8.86 °C | -1.25 °C | 34 mm |
| March | -3.17 °C | 5.34 °C | 80 mm |
| April | 2.69 °C | 12.05 °C | 97 mm |
| May | 8.78 °C | 19.09 °C | 100 mm |
| June | 14.21 °C | 24.12 °C | 98 mm |
| July | 16.86 °C | 27.11 °C | 101 mm |
| August | 16.46 °C | 26.27 °C | 102 mm |
| September | 12.34 °C | 22.01 °C | 83 mm |
| October | 6.69 °C | 15.02 °C | 88 mm |
| November | 0.99 °C | 8.34 °C | 70 mm |
| December | -3.78 °C | 2.08 °C | 68 mm |
| Annual | 4.6 °C | 13.3 °C | 947 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |