Climate twins of Harpers Ferry, WV

These are the US cities whose 12-month climate pattern most closely matches Harpers Ferry'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: Harpers Ferry vs its climate twin

Top match: Brookside, OH

Month Harpers Ferry Brookside
High Low Precip High Low Precip
January 41.2°F 21.1°F 3.13 in 38.7°F 21.7°F 3.44 in
February 44.2°F 23.0°F 2.41 in 41.8°F 23.1°F 2.67 in
March 52.5°F 29.0°F 3.72 in 51.2°F 29.8°F 3.78 in
April 64.7°F 38.6°F 3.60 in 64.5°F 39.6°F 3.52 in
May 73.5°F 48.8°F 4.57 in 73.9°F 50.1°F 4.20 in
June 82.0°F 58.2°F 4.16 in 81.4°F 59.3°F 4.26 in
July 86.1°F 62.4°F 4.28 in 85.0°F 63.8°F 4.09 in
August 84.8°F 60.9°F 3.27 in 84.6°F 62.7°F 3.19 in
September 78.1°F 53.7°F 4.40 in 78.7°F 56.1°F 3.50 in
October 66.8°F 42.0°F 3.41 in 66.4°F 44.0°F 2.94 in
November 55.7°F 32.1°F 3.08 in 53.7°F 33.7°F 2.90 in
December 44.8°F 25.3°F 3.46 in 43.2°F 26.9°F 3.39 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 →