Tolchester, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.4 °C (low) to 18.1 °C (high). Annual precipitation averages 1153.9 Millimeters. Tolchester is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.3 °C | 5.5 °C | 82.3 mm |
| February | -1.6 °C | 6.8 °C | 69.6 mm |
| March | 2.1 °C | 11.2 °C | 103.89 mm |
| April | 7.8 °C | 17.6 °C | 88.14 mm |
| May | 13.2 °C | 22.6 °C | 106.17 mm |
| June | 18.5 °C | 27.5 °C | 111 mm |
| July | 21.5 °C | 30 °C | 107.44 mm |
| August | 20.6 °C | 29.2 °C | 104.14 mm |
| September | 17 °C | 25.7 °C | 114.55 mm |
| October | 10.5 °C | 19.5 °C | 95.76 mm |
| November | 4.9 °C | 13.1 °C | 76.45 mm |
| December | 0.4 °C | 8 °C | 94.49 mm |
| Annual | 9.4 °C | 18.1 °C | 1153.93 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |