Climate twins of Harrisburg, OR

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

Top match: Chehalis, WA

Month Harrisburg Chehalis
High Low Precip High Low Precip
January 48.1°F 34.7°F 6.05 in 46.1°F 34.2°F 5.85 in
February 51.5°F 35.0°F 4.67 in 49.5°F 33.9°F 4.24 in
March 56.6°F 37.2°F 4.64 in 54.1°F 35.9°F 4.39 in
April 61.3°F 40.0°F 3.32 in 59.5°F 39.1°F 3.24 in
May 68.1°F 44.0°F 2.46 in 66.6°F 44.4°F 2.44 in
June 74.2°F 47.6°F 1.23 in 71.1°F 49.1°F 1.53 in
July 84.0°F 51.7°F 0.32 in 77.5°F 52.9°F 0.50 in
August 84.3°F 51.5°F 0.39 in 78.2°F 52.8°F 0.84 in
September 78.0°F 47.8°F 1.39 in 72.6°F 48.4°F 1.59 in
October 64.9°F 41.8°F 3.17 in 61.1°F 42.7°F 4.00 in
November 53.2°F 37.7°F 5.98 in 50.7°F 37.1°F 6.53 in
December 46.8°F 34.3°F 7.21 in 45.0°F 33.9°F 6.44 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 →