Marystown, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 3.5 °C (low) to 8.3 °C (high). Annual precipitation averages 1302 Millimeters. Marystown is located in USDA Plant Hardiness Zone 6a. 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 | -4.93 °C | 0.07 °C | 88 mm |
| February | -5.95 °C | -1.17 °C | 80 mm |
| March | -4.27 °C | 0.18 °C | 79 mm |
| April | -0.66 °C | 4.04 °C | 97 mm |
| May | 3.48 °C | 8.77 °C | 95 mm |
| June | 7.64 °C | 12.78 °C | 102 mm |
| July | 12.47 °C | 17.31 °C | 112 mm |
| August | 14.23 °C | 19.18 °C | 111 mm |
| September | 11.3 °C | 16.34 °C | 128 mm |
| October | 7.13 °C | 11.45 °C | 146 mm |
| November | 2.73 °C | 7.1 °C | 145 mm |
| December | -1.61 °C | 2.99 °C | 119 mm |
| Annual | 3.5 °C | 8.3 °C | 1302 mm |
| 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 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |