Powassan, Ontario climate data is summarized below. Average annual temperatures range from 0.1 °C (low) to 10.3 °C (high). Annual precipitation averages 650 Millimeters. Powassan is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.39 °C | -5.99 °C | 0 mm |
| February | -15.89 °C | -5.53 °C | 0 mm |
| March | -8.54 °C | 1.61 °C | 20 mm |
| April | -0.76 °C | 10.3 °C | 62 mm |
| May | 5.99 °C | 18.59 °C | 71 mm |
| June | 11.36 °C | 23.1 °C | 77 mm |
| July | 13.68 °C | 25.1 °C | 89 mm |
| August | 13.21 °C | 24.02 °C | 96 mm |
| September | 8.45 °C | 19.42 °C | 89 mm |
| October | 3.15 °C | 11.86 °C | 102 mm |
| November | -3.01 °C | 4.73 °C | 44 mm |
| December | -10.89 °C | -3.17 °C | 0 mm |
| Annual | 0.1 °C | 10.3 °C | 650 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |