Vienna, Maryland has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 47.2 °F (low) to 67.8 °F (high). Annual precipitation averages 45.2 Inches. Vienna is located in USDA Plant Hardiness Zone 7b. 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 | 27.7 °F | 45.8 °F | 3.28 in. |
| February | 28.6 °F | 48.5 °F | 2.9 in. |
| March | 34.9 °F | 55.7 °F | 4.02 in. |
| April | 44.8 °F | 67.3 °F | 3.51 in. |
| May | 54.3 °F | 75.9 °F | 3.74 in. |
| June | 63.5 °F | 84.5 °F | 4.38 in. |
| July | 68.4 °F | 88.8 °F | 4.16 in. |
| August | 66.1 °F | 86.5 °F | 4.63 in. |
| September | 60.0 °F | 81.1 °F | 4.01 in. |
| October | 48.6 °F | 70.6 °F | 3.67 in. |
| November | 38.2 °F | 59.2 °F | 3.11 in. |
| December | 31.6 °F | 50.1 °F | 3.76 in. |
| Annual | 47.2 °F | 67.8 °F | 45.17 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |