Massey, Ontario climate data is summarized below. Average annual temperatures range from 0.5 °C (low) to 10.4 °C (high). Annual precipitation averages 611 Millimeters. Massey is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.37 °C | -5.54 °C | 0 mm |
| February | -16.23 °C | -4.92 °C | 0 mm |
| March | -9.48 °C | 1.55 °C | 22 mm |
| April | -1.28 °C | 9.14 °C | 69 mm |
| May | 6.36 °C | 17.57 °C | 67 mm |
| June | 11.94 °C | 22.63 °C | 65 mm |
| July | 14.37 °C | 24.97 °C | 63 mm |
| August | 14.05 °C | 24.31 °C | 74 mm |
| September | 9.45 °C | 19.73 °C | 74 mm |
| October | 3.97 °C | 12.52 °C | 104 mm |
| November | -1.82 °C | 5.41 °C | 58 mm |
| December | -10.21 °C | -2.32 °C | 15 mm |
| Annual | 0.5 °C | 10.4 °C | 611 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |