Clinton, Ontario climate data is summarized below. Average annual temperatures range from 3.3 °C (low) to 12.6 °C (high). Annual precipitation averages 377 Millimeters. Clinton 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 | -8.57 °C | -1.98 °C | 1 mm |
| February | -10.57 °C | -2.49 °C | 0 mm |
| March | -4.93 °C | 4.25 °C | 23 mm |
| April | 1.68 °C | 12.35 °C | 24 mm |
| May | 7.92 °C | 19.38 °C | 50 mm |
| June | 12.76 °C | 23.74 °C | 58 mm |
| July | 14.87 °C | 26.04 °C | 73 mm |
| August | 14.5 °C | 25.38 °C | 59 mm |
| September | 10.58 °C | 21.51 °C | 40 mm |
| October | 5.89 °C | 14.47 °C | 27 mm |
| November | 0.38 °C | 7.56 °C | 15 mm |
| December | -4.54 °C | 1.22 °C | 7 mm |
| Annual | 3.3 °C | 12.6 °C | 377 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 |