| | Reston, VA | Collierville, TN | United States |
| Rainfall | 42.7 | 55.1 | 38.1 |
| Snowfall | 21.5 | 1.9 | 27.8 |
| Precipitation Days | 117.9 | 106 | 106.2 |
| Sunny | 197 | 216 | 205 |
| Avg. July High | 85.5 | 91 | 85.8 |
| Avg. Jan. Low | 23.5 | 28.9 | 21.7 |
| Comfort Index (higher=better) | 7.3 | 7.1 | 7 |
| UV Index | 4 | 4.8 | 4.3 |
| Elevation ft. | 331 | 381 | 2443 |