Climate twins of Portsmouth, VA

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

Top match: Society Hill, SC

Month Portsmouth Society Hill
High Low Precip High Low Precip
January 50.0°F 34.0°F 2.93 in 54.3°F 31.4°F 3.51 in
February 52.8°F 35.4°F 2.55 in 57.7°F 34.0°F 3.06 in
March 59.4°F 41.3°F 3.47 in 65.1°F 40.4°F 3.76 in
April 69.5°F 50.3°F 3.28 in 74.2°F 49.1°F 3.31 in
May 77.0°F 59.5°F 3.55 in 81.0°F 58.1°F 3.66 in
June 84.4°F 68.0°F 4.64 in 87.5°F 66.7°F 4.79 in
July 88.7°F 72.6°F 5.21 in 90.5°F 70.5°F 5.18 in
August 86.3°F 71.5°F 5.30 in 88.6°F 69.4°F 5.09 in
September 80.8°F 66.7°F 5.14 in 83.3°F 63.3°F 5.35 in
October 71.7°F 55.5°F 3.58 in 74.3°F 51.0°F 3.90 in
November 61.4°F 44.7°F 3.14 in 64.6°F 40.0°F 3.27 in
December 53.9°F 37.9°F 2.89 in 56.9°F 34.3°F 3.74 in

Cities that consider Portsmouth their climate twin

These US cities have Portsmouth in their top 3 most-similar list — meaning if you were to move from any of these places, Portsmouth would feel familiar.

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 →