Thurmont, Maryland has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 44.1 °F (low) to 64.3 °F (high). Annual precipitation averages 45.2 Inches. Thurmont 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 | 23.8 °F | 40.3 °F | 3.36 in. |
| February | 25.1 °F | 43.7 °F | 2.59 in. |
| March | 31.9 °F | 52.3 °F | 3.79 in. |
| April | 41.9 °F | 64.7 °F | 4.06 in. |
| May | 51.6 °F | 73.5 °F | 4.3 in. |
| June | 60.7 °F | 82.0 °F | 4.08 in. |
| July | 65.3 °F | 86.6 °F | 3.92 in. |
| August | 63.4 °F | 84.6 °F | 3.57 in. |
| September | 56.5 °F | 78.0 °F | 4.76 in. |
| October | 45.3 °F | 66.5 °F | 3.8 in. |
| November | 35.0 °F | 54.9 °F | 3.34 in. |
| December | 28.3 °F | 44.4 °F | 3.62 in. |
| Annual | 44.1 °F | 64.3 °F | 45.19 in. |
| 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 : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |