Rocky Harbour, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 32.4 °F (low) to 41.9 °F (high). Annual precipitation averages 32.8 Inches. Rocky Harbour is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -23.3 °F | -20.3 °F | 381 in. |
| February | -23.6 °F | -20.5 °F | 76.2 in. |
| March | -22.7 °F | -19.6 °F | 609.6 in. |
| April | -19.7 °F | -17.1 °F | 1193.8 in. |
| May | -17.1 °F | -13.8 °F | 1981.2 in. |
| June | -14.3 °F | -10.8 °F | 1727.2 in. |
| July | -11.7 °F | -8.2 °F | 2311.4 in. |
| August | -11.2 °F | -8 °F | 2921 in. |
| September | -13.2 °F | -10.3 °F | 3200.4 in. |
| October | -15.7 °F | -13.4 °F | 2921 in. |
| November | -18.4 °F | -16.1 °F | 2438.4 in. |
| December | -21.1 °F | -18.6 °F | 1422.4 in. |
| Annual | 32.4 °F | 41.9 °F | 32.83 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |