Harbour Breton, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 36.5 °F (low) to 46.8 °F (high). Annual precipitation averages 49.7 Inches. Harbour Breton is located in USDA Plant Hardiness Zone . The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -21.4 °F | -18.3 °F | 2057.4 in. |
| February | -22 °F | -18.8 °F | 1930.4 in. |
| March | -20.9 °F | -17.9 °F | 1752.6 in. |
| April | -18.5 °F | -15.4 °F | 2286 in. |
| May | -16.1 °F | -12.5 °F | 2438.4 in. |
| June | -13.6 °F | -10.2 °F | 2565.4 in. |
| July | -11 °F | -7.7 °F | 2768.6 in. |
| August | -10.3 °F | -6.8 °F | 2768.6 in. |
| September | -12.1 °F | -8.6 °F | 3175 in. |
| October | -14.5 °F | -11.6 °F | 3784.6 in. |
| November | -16.9 °F | -14.2 °F | 3556 in. |
| December | -19.4 °F | -16.6 °F | 2997.2 in. |
| Annual | 36.5 °F | 46.8 °F | 49.73 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | |
| Current Drought Conditions | Normal |