Brewster, New York has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.8 °C (low) to 15.8 °C (high). Annual precipitation averages 1244.3 Millimeters. Brewster is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.6 °C | 2.2 °C | 95.5 mm |
| February | -6.5 °C | 3.9 °C | 66.29 mm |
| March | -2.5 °C | 8.3 °C | 97.54 mm |
| April | 3.4 °C | 15.4 °C | 97.28 mm |
| May | 8.9 °C | 21.2 °C | 85.09 mm |
| June | 14.1 °C | 25.7 °C | 100.58 mm |
| July | 17 °C | 28.6 °C | 116.59 mm |
| August | 16.3 °C | 27.5 °C | 137.92 mm |
| September | 12.1 °C | 23.7 °C | 113.79 mm |
| October | 5.7 °C | 17.2 °C | 122.68 mm |
| November | 0.4 °C | 10.9 °C | 106.93 mm |
| December | -4.1 °C | 4.9 °C | 104.14 mm |
| Annual | 4.8 °C | 15.8 °C | 1244.33 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |