MacTier, Ontario climate data is summarized below. Average annual temperatures range from 0.4 °C (low) to 11.1 °C (high). Annual precipitation averages 708 Millimeters. MacTier is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14 °C | -4.29 °C | 0 mm |
| February | -15.21 °C | -4.37 °C | 0 mm |
| March | -8.43 °C | 2.22 °C | 31 mm |
| April | -1.04 °C | 10.61 °C | 68 mm |
| May | 5.54 °C | 18.55 °C | 80 mm |
| June | 10.98 °C | 23.07 °C | 89 mm |
| July | 13.47 °C | 25.28 °C | 88 mm |
| August | 12.86 °C | 24.57 °C | 83 mm |
| September | 8.57 °C | 20.2 °C | 85 mm |
| October | 3.77 °C | 13.07 °C | 110 mm |
| November | -2.09 °C | 6.16 °C | 64 mm |
| December | -9.27 °C | -1.47 °C | 10 mm |
| Annual | 0.4 °C | 11.1 °C | 708 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |