Climate twins of Portland, IN
These are the US cities whose 12-month climate pattern most closely matches Portland'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: Portland vs its climate twin
Top match: Attica, OH
| Month | Portland | Attica | ||||
|---|---|---|---|---|---|---|
| High | Low | Precip | High | Low | Precip | |
| January | 33.8°F | 17.0°F | 2.82 in | 33.3°F | 18.7°F | 2.57 in |
| February | 37.6°F | 19.0°F | 2.71 in | 36.4°F | 20.5°F | 2.24 in |
| March | 48.2°F | 27.7°F | 2.80 in | 46.5°F | 28.8°F | 2.73 in |
| April | 61.6°F | 37.8°F | 3.62 in | 60.0°F | 38.7°F | 3.82 in |
| May | 71.7°F | 49.2°F | 4.31 in | 71.5°F | 50.4°F | 4.10 in |
| June | 80.4°F | 58.7°F | 4.55 in | 80.5°F | 59.9°F | 4.20 in |
| July | 83.7°F | 61.9°F | 4.07 in | 83.9°F | 63.6°F | 3.91 in |
| August | 81.9°F | 59.6°F | 3.83 in | 82.5°F | 61.8°F | 3.54 in |
| September | 76.5°F | 52.3°F | 2.97 in | 76.7°F | 54.3°F | 3.32 in |
| October | 64.3°F | 41.1°F | 2.85 in | 63.8°F | 42.9°F | 2.76 in |
| November | 50.5°F | 31.1°F | 3.01 in | 49.7°F | 33.4°F | 2.89 in |
| December | 38.9°F | 22.9°F | 2.39 in | 38.2°F | 24.5°F | 2.61 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 →