Island Harbour, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 36.6 °F (low) to 42.8 °F (high). Annual precipitation averages 32.5 Inches. Island Harbour is located in USDA Plant Hardiness Zone . The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -20.9 °F | -18.7 °F | 863.6 in. |
| February | -21.3 °F | -19.1 °F | 635 in. |
| March | -20.5 °F | -18.6 °F | 635 in. |
| April | -18.7 °F | -17.2 °F | 1092.2 in. |
| May | -16.7 °F | -14.9 °F | 1778 in. |
| June | -14.1 °F | -12.1 °F | 1879.6 in. |
| July | -11.2 °F | -9.1 °F | 2235.2 in. |
| August | -10.4 °F | -8.5 °F | 2438.4 in. |
| September | -12 °F | -10 °F | 2667 in. |
| October | -14.3 °F | -12.6 °F | 2590.8 in. |
| November | -16.9 °F | -15 °F | 2387.6 in. |
| December | -19.3 °F | -17.3 °F | 1778 in. |
| Annual | 36.6 °F | 42.8 °F | 32.51 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | |
| Current Drought Conditions | Normal |