Island Harbour, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 2.6 °C (low) to 6 °C (high). Annual precipitation averages 826 Millimeters. 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 | -5.56 °C | -1.68 °C | 34 mm |
| February | -6.26 °C | -2.4 °C | 25 mm |
| March | -4.87 °C | -1.47 °C | 25 mm |
| April | -1.69 °C | 1.03 °C | 43 mm |
| May | 1.92 °C | 5.1 °C | 70 mm |
| June | 6.7 °C | 10.18 °C | 74 mm |
| July | 11.78 °C | 15.54 °C | 88 mm |
| August | 13.29 °C | 16.75 °C | 96 mm |
| September | 10.4 °C | 13.98 °C | 105 mm |
| October | 6.23 °C | 9.25 °C | 102 mm |
| November | 1.56 °C | 4.94 °C | 94 mm |
| December | -2.75 °C | 0.79 °C | 70 mm |
| Annual | 2.6 °C | 6 °C | 826 mm |
| 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 |