Climate twins of St. Charles, AR
These are the US cities whose 12-month climate pattern most closely matches St. Charles'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: St. Charles vs its climate twin
Top match: Haynesville, LA
| Month | St. Charles | Haynesville | ||||
|---|---|---|---|---|---|---|
| High | Low | Precip | High | Low | Precip | |
| January | 50.0°F | 32.5°F | 4.36 in | 55.6°F | 32.0°F | 5.15 in |
| February | 54.7°F | 35.6°F | 4.70 in | 59.7°F | 35.3°F | 5.26 in |
| March | 63.6°F | 43.5°F | 5.73 in | 67.5°F | 41.7°F | 5.68 in |
| April | 72.4°F | 51.6°F | 5.86 in | 75.2°F | 49.2°F | 5.89 in |
| May | 80.0°F | 60.7°F | 4.49 in | 81.9°F | 58.8°F | 4.74 in |
| June | 87.0°F | 68.7°F | 3.54 in | 88.6°F | 66.4°F | 4.04 in |
| July | 90.1°F | 71.6°F | 3.80 in | 91.7°F | 69.9°F | 4.02 in |
| August | 89.7°F | 70.1°F | 2.76 in | 92.0°F | 69.0°F | 3.28 in |
| September | 84.9°F | 63.0°F | 3.02 in | 86.9°F | 62.4°F | 3.73 in |
| October | 74.6°F | 50.9°F | 3.79 in | 76.6°F | 50.2°F | 4.64 in |
| November | 62.4°F | 41.5°F | 4.55 in | 65.3°F | 40.3°F | 4.64 in |
| December | 52.7°F | 35.3°F | 5.28 in | 57.5°F | 34.1°F | 5.92 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 →