Climate twins of Friday Harbor, WA

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

Top match: Colton, WA

Month Friday Harbor Colton
High Low Precip High Low Precip
January 47.1°F 37.1°F 2.69 in 37.6°F 27.8°F 2.15 in
February 48.5°F 36.5°F 1.54 in 41.6°F 29.2°F 1.59 in
March 52.6°F 38.4°F 1.35 in 49.3°F 32.9°F 1.95 in
April 57.4°F 40.7°F 1.01 in 56.4°F 37.2°F 1.79 in
May 63.7°F 44.3°F 1.14 in 65.4°F 43.7°F 1.41 in
June 68.4°F 48.1°F 0.75 in 71.9°F 47.7°F 1.17 in
July 72.4°F 50.0°F 0.48 in 83.1°F 50.9°F 0.39 in
August 73.3°F 50.0°F 0.70 in 83.4°F 50.4°F 0.49 in
September 68.1°F 47.9°F 1.04 in 74.2°F 45.4°F 0.65 in
October 58.5°F 44.0°F 2.34 in 59.2°F 37.6°F 1.59 in
November 51.0°F 39.8°F 2.98 in 44.7°F 32.5°F 2.14 in
December 46.3°F 36.8°F 2.45 in 36.6°F 26.9°F 2.21 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 →