| | Rockville, MD | Damascus, MD | United States |
| Rainfall | 42.2 | 43.8 | 38.1 |
| Snowfall | 18.2 | 25.6 | 27.8 |
| Precipitation Days | 112.3 | 117.1 | 106.2 |
| Sunny | 203 | 202 | 205 |
| Avg. July High | 84.8 | 84.9 | 85.8 |
| Avg. Jan. Low | 25.1 | 25.3 | 21.7 |
| Comfort Index (higher=better) | 7.4 | 7.3 | 7 |
| UV Index | 4.1 | 4.1 | 4.3 |
| Elevation ft. | 456 | 833 | 2443 |