Metcalfe, Ontario climate data is summarized below. Average annual temperatures range from 2.1 °C (low) to 11.9 °C (high). Annual precipitation averages 435 Millimeters. Metcalfe 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 | -13.18 °C | -4.55 °C | 0 mm |
| February | -12.96 °C | -3.78 °C | 0 mm |
| March | -6.49 °C | 3.28 °C | 14 mm |
| April | 1.55 °C | 12.21 °C | 38 mm |
| May | 8.04 °C | 19.95 °C | 47 mm |
| June | 13.13 °C | 24.06 °C | 58 mm |
| July | 15.64 °C | 26.65 °C | 94 mm |
| August | 14.75 °C | 25.64 °C | 80 mm |
| September | 9.93 °C | 21.18 °C | 47 mm |
| October | 4.53 °C | 13.7 °C | 33 mm |
| November | -1.48 °C | 6.56 °C | 19 mm |
| December | -8.55 °C | -1.69 °C | 5 mm |
| Annual | 2.1 °C | 11.9 °C | 435 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 |