Riverhead, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 2.5 °C (low) to 8.7 °C (high). Annual precipitation averages 1194 Millimeters. Riverhead is located in USDA Plant Hardiness Zone 5b. 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 | -5.9 °C | 0.08 °C | 86 mm |
| February | -6.83 °C | -0.99 °C | 87 mm |
| March | -5.17 °C | 0.16 °C | 81 mm |
| April | -1.5 °C | 4.54 °C | 98 mm |
| May | 2.61 °C | 9.53 °C | 90 mm |
| June | 6.67 °C | 13.94 °C | 83 mm |
| July | 11.73 °C | 18.88 °C | 93 mm |
| August | 13.01 °C | 19.87 °C | 85 mm |
| September | 9.82 °C | 16.73 °C | 107 mm |
| October | 6.04 °C | 11.52 °C | 132 mm |
| November | 1.87 °C | 7.08 °C | 133 mm |
| December | -2.46 °C | 2.74 °C | 119 mm |
| Annual | 2.5 °C | 8.7 °C | 1194 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |