Chester, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 49.7 °F (low) to 64.8 °F (high). Annual precipitation averages 44.3 Inches. Chester 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 Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 28.8 °F | 42.5 °F | 3.12 in. |
| February | 29.8 °F | 44.6 °F | 2.67 in. |
| March | 36.3 °F | 52.4 °F | 4.08 in. |
| April | 46.6 °F | 63.9 °F | 3.38 in. |
| May | 56.5 °F | 73.1 °F | 4.01 in. |
| June | 66.0 °F | 81.8 °F | 4.17 in. |
| July | 71.7 °F | 86.3 °F | 4.3 in. |
| August | 69.7 °F | 84.7 °F | 4.08 in. |
| September | 63.2 °F | 78.4 °F | 4.26 in. |
| October | 51.9 °F | 67.3 °F | 3.71 in. |
| November | 41.7 °F | 56.0 °F | 2.92 in. |
| December | 33.7 °F | 46.9 °F | 3.64 in. |
| Annual | 49.7 °F | 64.8 °F | 44.34 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |