Climate twins of Sully, IA
These are the US cities whose 12-month climate pattern most closely matches Sully's. Each "twin" must be at least 140 miles away to avoid trivial near-neighbor matches. Similarity is computed across all 24 monthly metrics (12 average temperatures + 12 average precipitations), normalized so temperature and precipitation contribute equally.
Side-by-side: Sully vs its climate twin
Top match: Woodman, WI
| Month | Sully | Woodman | ||||
|---|---|---|---|---|---|---|
| High | Low | Precip | High | Low | Precip | |
| January | 28.3°F | 10.2°F | 1.10 in | 27.4°F | 7.7°F | 1.24 in |
| February | 33.0°F | 13.6°F | 1.55 in | 31.6°F | 12.3°F | 1.22 in |
| March | 46.1°F | 24.7°F | 2.22 in | 44.3°F | 23.9°F | 2.10 in |
| April | 59.4°F | 35.1°F | 3.90 in | 58.0°F | 36.2°F | 4.05 in |
| May | 69.9°F | 47.1°F | 5.09 in | 69.4°F | 47.7°F | 4.59 in |
| June | 79.5°F | 57.8°F | 5.53 in | 78.0°F | 58.3°F | 5.50 in |
| July | 83.3°F | 61.8°F | 3.96 in | 81.7°F | 62.2°F | 4.35 in |
| August | 81.2°F | 59.2°F | 4.37 in | 80.0°F | 60.7°F | 4.17 in |
| September | 75.2°F | 50.2°F | 3.71 in | 73.3°F | 51.5°F | 3.68 in |
| October | 62.3°F | 38.2°F | 3.21 in | 60.6°F | 40.1°F | 2.76 in |
| November | 46.8°F | 26.4°F | 1.95 in | 45.4°F | 27.0°F | 2.20 in |
| December | 34.0°F | 16.3°F | 1.60 in | 33.1°F | 15.7°F | 1.55 in |
How this is computed
Each city is represented by a 24-dimensional vector: 12 monthly average temperatures and 12 monthly average precipitations. Each dimension is z-score normalized across the population of US cities, so that temperature variance and precipitation variance contribute proportionally. Distance between cities is Euclidean. We filter out cities within 2° latitude/longitude (~140 miles) so that "twins" mean climatically similar but geographically distinct — not just the neighboring town. Full methodology →