Mastic, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 6.5 °C (low) to 16.1 °C (high). Annual precipitation averages 1192.5 Millimeters. Mastic is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.9 °C | 4.1 °C | 96.52 mm |
| February | -4.3 °C | 4.9 °C | 87.12 mm |
| March | -0.9 °C | 8.6 °C | 122.68 mm |
| April | 4.1 °C | 14.4 °C | 106.17 mm |
| May | 9.6 °C | 19.8 °C | 88.39 mm |
| June | 14.9 °C | 24.8 °C | 98.3 mm |
| July | 18.4 °C | 28 °C | 78.49 mm |
| August | 17.9 °C | 27.3 °C | 93.47 mm |
| September | 14.2 °C | 23.8 °C | 89.41 mm |
| October | 8.1 °C | 17.7 °C | 117.6 mm |
| November | 2.6 °C | 12.2 °C | 95.5 mm |
| December | -1.7 °C | 7 °C | 118.87 mm |
| Annual | 6.5 °C | 16.1 °C | 1192.52 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |