Postville, Newfoundland and Labrador climate data is summarized below. Average annual temperatures range from 21.5 °F (low) to 37.7 °F (high). Annual precipitation averages 19.5 Inches. Postville is located in USDA Plant Hardiness Zone 2a. 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 | -28.9 °F | -24.2 °F | 0 in. |
| February | -29.3 °F | -23.7 °F | 0 in. |
| March | -28 °F | -21.7 °F | 0 in. |
| April | -23.2 °F | -17.9 °F | 0 in. |
| May | -19.5 °F | -15.2 °F | 1320.8 in. |
| June | -15.2 °F | -9.6 °F | 2108.2 in. |
| July | -12.7 °F | -7 °F | 2413 in. |
| August | -12.6 °F | -7 °F | 1955.8 in. |
| September | -15.6 °F | -10.4 °F | 2463.8 in. |
| October | -18 °F | -14.5 °F | 1828.8 in. |
| November | -22.4 °F | -18.5 °F | 482.6 in. |
| December | -26.9 °F | -22.5 °F | 0 in. |
| Annual | 21.5 °F | 37.7 °F | 19.49 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 2a : -50°F to -45°F |
| Current Drought Conditions | Moderate Drought |