Mount Forest, Ontario climate data is summarized below. Average annual temperatures range from 2 °C (low) to 11.1 °C (high). Annual precipitation averages 441 Millimeters. Mount Forest is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.55 °C | -3.59 °C | 0 mm |
| February | -11.85 °C | -4.08 °C | 0 mm |
| March | -5.84 °C | 2.92 °C | 21 mm |
| April | 0.34 °C | 10.68 °C | 29 mm |
| May | 6.54 °C | 17.88 °C | 54 mm |
| June | 11.45 °C | 22.29 °C | 72 mm |
| July | 13.57 °C | 24.57 °C | 79 mm |
| August | 13.29 °C | 23.98 °C | 94 mm |
| September | 9.52 °C | 19.89 °C | 42 mm |
| October | 4.63 °C | 12.97 °C | 26 mm |
| November | -1.13 °C | 6.1 °C | 16 mm |
| December | -6.37 °C | -0.59 °C | 8 mm |
| Annual | 2 °C | 11.1 °C | 441 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |