Hanover, Ontario climate data is summarized below. Average annual temperatures range from 2.5 °C (low) to 12 °C (high). Annual precipitation averages 541 Millimeters. Hanover 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 | -9.9 °C | -2.84 °C | 0 mm |
| February | -11.37 °C | -3.36 °C | 0 mm |
| March | -5.74 °C | 3.52 °C | 27 mm |
| April | 0.93 °C | 11.7 °C | 46 mm |
| May | 6.95 °C | 18.92 °C | 72 mm |
| June | 11.91 °C | 23.43 °C | 78 mm |
| July | 14.13 °C | 25.64 °C | 68 mm |
| August | 13.78 °C | 24.9 °C | 79 mm |
| September | 9.85 °C | 20.72 °C | 69 mm |
| October | 5.21 °C | 13.82 °C | 68 mm |
| November | -0.39 °C | 7.03 °C | 34 mm |
| December | -5.86 °C | 0.17 °C | 0 mm |
| Annual | 2.5 °C | 12 °C | 541 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 |