Climate twins of Madison, IL
These are the US cities whose 12-month climate pattern most closely matches Madison'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: Madison vs its climate twin
Top match: St. Elizabeth, MO
| Month | Madison | St. Elizabeth | ||||
|---|---|---|---|---|---|---|
| High | Low | Precip | High | Low | Precip | |
| January | 40.2°F | 24.1°F | 2.46 in | 41.1°F | 20.7°F | 2.40 in |
| February | 45.6°F | 27.6°F | 1.96 in | 46.5°F | 24.8°F | 2.21 in |
| March | 56.3°F | 36.0°F | 3.27 in | 56.3°F | 33.7°F | 3.32 in |
| April | 67.5°F | 45.5°F | 4.48 in | 66.9°F | 43.7°F | 4.79 in |
| May | 76.7°F | 56.5°F | 4.84 in | 75.2°F | 54.6°F | 4.93 in |
| June | 85.7°F | 64.7°F | 4.36 in | 83.1°F | 63.5°F | 4.15 in |
| July | 89.0°F | 68.8°F | 3.70 in | 87.9°F | 67.5°F | 3.99 in |
| August | 87.8°F | 66.1°F | 3.68 in | 87.2°F | 65.8°F | 3.69 in |
| September | 80.7°F | 57.1°F | 3.36 in | 79.8°F | 56.7°F | 3.86 in |
| October | 69.4°F | 46.1°F | 3.07 in | 69.0°F | 46.1°F | 3.34 in |
| November | 55.3°F | 35.9°F | 3.34 in | 55.6°F | 34.6°F | 3.64 in |
| December | 44.3°F | 28.6°F | 2.32 in | 44.7°F | 25.9°F | 2.64 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 →