Grand Falls-Windsor, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 31.9 °F (low) to 46.1 °F (high). Annual precipitation averages 31.2 Inches. Grand Falls-Windsor 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 | -23.7 °F | -19.8 °F | 508 in. |
| February | -24.1 °F | -19.9 °F | 660.4 in. |
| March | -23 °F | -18.9 °F | 533.4 in. |
| April | -19.7 °F | -15.8 °F | 1219.2 in. |
| May | -17 °F | -11.9 °F | 1828.8 in. |
| June | -14.2 °F | -8.8 °F | 1955.8 in. |
| July | -11.4 °F | -5.7 °F | 2184.4 in. |
| August | -11.5 °F | -6.1 °F | 2641.6 in. |
| September | -13.6 °F | -8.7 °F | 2590.8 in. |
| October | -16 °F | -12.3 °F | 2616.2 in. |
| November | -18.4 °F | -15.3 °F | 2184.4 in. |
| December | -21.2 °F | -18.1 °F | 1193.8 in. |
| Annual | 31.9 °F | 46.1 °F | 31.19 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |