Thiells, New York has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.8 °C (low) to 16.6 °C (high). Annual precipitation averages 1257.3 Millimeters. Thiells 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 | -6.2 °C | 3.1 °C | 93.47 mm |
| February | -5.2 °C | 4.7 °C | 69.6 mm |
| March | -1.3 °C | 9.1 °C | 104.65 mm |
| April | 4.4 °C | 16.2 °C | 99.82 mm |
| May | 9.8 °C | 21.8 °C | 93.98 mm |
| June | 14.9 °C | 26.6 °C | 120.9 mm |
| July | 17.8 °C | 29.3 °C | 110.49 mm |
| August | 17 °C | 28.3 °C | 123.7 mm |
| September | 12.9 °C | 24.6 °C | 116.08 mm |
| October | 6.6 °C | 17.9 °C | 115.82 mm |
| November | 1.4 °C | 11.6 °C | 100.33 mm |
| December | -2.7 °C | 5.8 °C | 108.46 mm |
| Annual | 5.8 °C | 16.6 °C | 1257.3 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |