Darnestown, Maryland has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 45.5 °F (low) to 65.3 °F (high). Annual precipitation averages 45.1 Inches. Darnestown is located in USDA Plant Hardiness Zone 7b. 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 | 25.2 °F | 42.2 °F | 3.05 in. |
| February | 26.7 °F | 45.4 °F | 2.71 in. |
| March | 33.4 °F | 53.9 °F | 3.88 in. |
| April | 43.5 °F | 65.9 °F | 3.42 in. |
| May | 53.3 °F | 74.2 °F | 4.46 in. |
| June | 62.0 °F | 82.5 °F | 4.5 in. |
| July | 66.9 °F | 86.8 °F | 4.19 in. |
| August | 65.1 °F | 85.1 °F | 3.52 in. |
| September | 58.4 °F | 78.3 °F | 4.48 in. |
| October | 46.3 °F | 66.9 °F | 3.92 in. |
| November | 36.3 °F | 56.0 °F | 3.28 in. |
| December | 29.4 °F | 46.1 °F | 3.64 in. |
| Annual | 45.5 °F | 65.3 °F | 45.05 in. |
| 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 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |