Smyrna, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2 °C (low) to 14 °C (high). Annual precipitation averages 1126.2 Millimeters. Smyrna is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.7 °C | -0.3 °C | 75.18 mm |
| February | -10.1 °C | 1.1 °C | 66.04 mm |
| March | -6.2 °C | 5.6 °C | 84.84 mm |
| April | 0.3 °C | 13.2 °C | 89.41 mm |
| May | 6.6 °C | 20.3 °C | 95.5 mm |
| June | 11.7 °C | 24.8 °C | 119.38 mm |
| July | 14.2 °C | 27.2 °C | 113.03 mm |
| August | 13.3 °C | 26.4 °C | 108.71 mm |
| September | 9.3 °C | 22.7 °C | 99.57 mm |
| October | 3.7 °C | 15.6 °C | 102.36 mm |
| November | -1.6 °C | 8.4 °C | 84.33 mm |
| December | -6.2 °C | 2.4 °C | 87.88 mm |
| Annual | 2 °C | 14 °C | 1126.23 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |