| | Greenwich, CT | Rockville, MD | United States |
| Rainfall | 50.9 | 42.2 | 38.1 |
| Snowfall | 29.8 | 18.2 | 27.8 |
| Precipitation Days | 123.8 | 112.3 | 106.2 |
| Sunny | 190 | 203 | 205 |
| Avg. July High | 83.9 | 84.8 | 85.8 |
| Avg. Jan. Low | 21.2 | 25.1 | 21.7 |
| Comfort Index (higher=better) | 7.1 | 7.4 | 7 |
| UV Index | 3.4 | 4.1 | 4.3 |
| Elevation ft. | 113 | 456 | 2443 |