Castleton-on-Hudson, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 39.9 °F (low) to 59.5 °F (high). Annual precipitation averages 41.3 Inches. Castleton-on-Hudson is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.7 °F | 33.2 °F | 2.66 in. |
| February | 18.0 °F | 36.2 °F | 2.19 in. |
| March | 26.3 °F | 45.3 °F | 2.92 in. |
| April | 37.5 °F | 59.2 °F | 3.18 in. |
| May | 48.4 °F | 71.0 °F | 3.4 in. |
| June | 57.7 °F | 79.1 °F | 4.44 in. |
| July | 62.4 °F | 83.4 °F | 4.37 in. |
| August | 60.9 °F | 81.6 °F | 4.07 in. |
| September | 53.0 °F | 74.7 °F | 3.93 in. |
| October | 42.1 °F | 62.0 °F | 4.03 in. |
| November | 32.5 °F | 49.5 °F | 2.87 in. |
| December | 23.8 °F | 38.5 °F | 3.21 in. |
| Annual | 39.9 °F | 59.5 °F | 41.27 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |