San Mar, Maryland has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.9 °F (low) to 64.7 °F (high). Annual precipitation averages 42.3 Inches. San Mar 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 24.0 °F | 40.7 °F | 3.05 in. |
| February | 24.9 °F | 44.3 °F | 2.45 in. |
| March | 32.3 °F | 52.7 °F | 3.62 in. |
| April | 41.9 °F | 65.1 °F | 3.78 in. |
| May | 51.5 °F | 73.9 °F | 4.31 in. |
| June | 60.5 °F | 82.6 °F | 3.77 in. |
| July | 64.8 °F | 87.0 °F | 3.71 in. |
| August | 63.1 °F | 85.3 °F | 3.4 in. |
| September | 56.0 °F | 78.3 °F | 4.09 in. |
| October | 45.2 °F | 66.7 °F | 3.61 in. |
| November | 35.0 °F | 55.1 °F | 3.21 in. |
| December | 27.8 °F | 44.3 °F | 3.29 in. |
| Annual | 43.9 °F | 64.7 °F | 42.29 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| 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 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |