Climate twins of San Anselmo, CA

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

Top match: Sonora, CA

Month San Anselmo Sonora
High Low Precip High Low Precip
January 56.9°F 42.6°F 7.13 in 55.7°F 32.8°F 6.32 in
February 61.1°F 44.0°F 6.94 in 58.2°F 34.2°F 5.50 in
March 64.8°F 45.5°F 4.42 in 62.1°F 37.0°F 5.37 in
April 67.8°F 47.5°F 1.99 in 66.7°F 39.7°F 3.03 in
May 72.0°F 50.6°F 0.94 in 75.6°F 45.5°F 1.54 in
June 77.9°F 53.5°F 0.15 in 85.3°F 50.8°F 0.34 in
July 80.9°F 54.9°F 0.00 in 92.8°F 56.8°F 0.03 in
August 81.3°F 55.5°F 0.05 in 91.9°F 55.5°F 0.07 in
September 80.7°F 54.4°F 0.07 in 86.7°F 50.8°F 0.20 in
October 74.9°F 51.4°F 1.46 in 76.2°F 43.0°F 1.64 in
November 64.6°F 46.0°F 3.49 in 63.2°F 36.4°F 3.24 in
December 57.1°F 42.1°F 7.81 in 55.1°F 32.4°F 5.51 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 →