Climate twins of Rancho Cucamonga, CA

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

Top match: Newman, CA

Month Rancho Cucamonga Newman
High Low Precip High Low Precip
January 67.7°F 44.6°F 2.57 in 60.1°F 38.2°F 2.66 in
February 68.1°F 46.2°F 3.07 in 66.6°F 40.8°F 2.23 in
March 71.7°F 48.7°F 1.64 in 73.0°F 43.6°F 1.76 in
April 75.7°F 51.1°F 0.76 in 79.7°F 46.3°F 0.71 in
May 79.8°F 55.6°F 0.30 in 88.0°F 52.1°F 0.45 in
June 86.4°F 60.0°F 0.02 in 95.7°F 57.5°F 0.07 in
July 93.8°F 64.7°F 0.05 in 100.0°F 61.6°F 0.00 in
August 94.9°F 65.2°F 0.03 in 98.2°F 60.4°F 0.00 in
September 91.3°F 63.8°F 0.10 in 94.9°F 57.3°F 0.04 in
October 82.6°F 57.1°F 0.41 in 85.1°F 50.0°F 0.59 in
November 74.7°F 49.0°F 0.80 in 70.7°F 42.4°F 1.06 in
December 66.9°F 43.6°F 1.89 in 60.4°F 37.8°F 2.14 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 →