Cobourg, Ontario climate data is summarized below. Average annual temperatures range from 39.1 °F (low) to 52.4 °F (high). Annual precipitation averages 24.6 Inches. Cobourg is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -22.5 °F | -18.4 °F | 304.8 in. |
| February | -23.1 °F | -18.7 °F | 203.2 in. |
| March | -19.9 °F | -15.8 °F | 1143 in. |
| April | -16.6 °F | -12.5 °F | 1752.6 in. |
| May | -13.6 °F | -9.3 °F | 1701.8 in. |
| June | -10.6 °F | -6.5 °F | 1854.2 in. |
| July | -8.9 °F | -4.6 °F | 2057.4 in. |
| August | -8.9 °F | -4.6 °F | 2082.8 in. |
| September | -11.2 °F | -6.6 °F | 1219.2 in. |
| October | -14 °F | -10.1 °F | 1422.4 in. |
| November | -17.3 °F | -13.5 °F | 1168.4 in. |
| December | -20.4 °F | -17 °F | 965.2 in. |
| Annual | 39.1 °F | 52.4 °F | 24.6 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |