Erin, Ontario climate data is summarized below. Average annual temperatures range from 2.6 °C (low) to 11.9 °C (high). Annual precipitation averages 808 Millimeters. Erin is located in USDA Plant Hardiness Zone 5b. 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 | -10.04 °C | -2.92 °C | 9 mm |
| February | -11.14 °C | -3.17 °C | 5 mm |
| March | -5.55 °C | 3.66 °C | 38 mm |
| April | 0.81 °C | 11.41 °C | 76 mm |
| May | 7.28 °C | 18.73 °C | 112 mm |
| June | 12.32 °C | 23.19 °C | 115 mm |
| July | 14.85 °C | 25.88 °C | 115 mm |
| August | 14.2 °C | 25.02 °C | 122 mm |
| September | 10.25 °C | 20.83 °C | 72 mm |
| October | 4.85 °C | 13.62 °C | 68 mm |
| November | -0.89 °C | 6.82 °C | 45 mm |
| December | -5.95 °C | -0.14 °C | 31 mm |
| Annual | 2.6 °C | 11.9 °C | 808 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |