Exeter, Ontario climate data is summarized below. Average annual temperatures range from 3.6 °C (low) to 13.3 °C (high). Annual precipitation averages 391 Millimeters. Exeter is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.71 °C | -1.67 °C | 2 mm |
| February | -10.68 °C | -1.96 °C | 0 mm |
| March | -4.7 °C | 5.08 °C | 19 mm |
| April | 2.04 °C | 13.18 °C | 25 mm |
| May | 8.28 °C | 20.31 °C | 46 mm |
| June | 13.21 °C | 24.63 °C | 69 mm |
| July | 15.41 °C | 26.8 °C | 83 mm |
| August | 14.95 °C | 26.2 °C | 62 mm |
| September | 10.96 °C | 22.3 °C | 43 mm |
| October | 5.95 °C | 15.04 °C | 23 mm |
| November | 0.26 °C | 7.92 °C | 14 mm |
| December | -4.46 °C | 1.55 °C | 5 mm |
| Annual | 3.6 °C | 13.3 °C | 391 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |