Truro, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 7.2 °C (low) to 14.9 °C (high). Annual precipitation averages 1155.5 Millimeters. Truro is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.4 °C | 3.7 °C | 103.12 mm |
| February | -3 °C | 4.3 °C | 86.11 mm |
| March | -0.4 °C | 7.2 °C | 118.62 mm |
| April | 4.4 °C | 12.2 °C | 100.33 mm |
| May | 9.3 °C | 17.7 °C | 78.49 mm |
| June | 14.4 °C | 23.1 °C | 84.07 mm |
| July | 18.3 °C | 26.9 °C | 67.31 mm |
| August | 17.8 °C | 26.3 °C | 82.55 mm |
| September | 14.7 °C | 22.6 °C | 99.82 mm |
| October | 9.4 °C | 16.7 °C | 113.03 mm |
| November | 4.4 °C | 11.3 °C | 107.19 mm |
| December | -0.1 °C | 6.8 °C | 114.81 mm |
| Annual | 7.2 °C | 14.9 °C | 1155.45 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |