Climate twins of Rancho Santa Margarita, CA

These are the US cities whose 12-month climate pattern most closely matches Rancho Santa Margarita'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.

Rank 1 closest
Isleton, CA
similarity distance: 2.105 (lower = more similar)
Rank 2 closest
Brentwood, CA
similarity distance: 2.105 (lower = more similar)
Rank 3 closest
Antioch, CA
similarity distance: 2.105 (lower = more similar)

Side-by-side: Rancho Santa Margarita vs its climate twin

Top match: Isleton, CA

Month Rancho Santa Margarita Isleton
High Low Precip High Low Precip
January 69.0°F 48.6°F 2.67 in 55.7°F 40.3°F 2.68 in
February 70.5°F 47.9°F 3.47 in 60.8°F 43.9°F 2.36 in
March 73.1°F 49.7°F 1.70 in 66.5°F 46.6°F 1.95 in
April 76.4°F 51.9°F 0.85 in 72.1°F 49.5°F 0.91 in
May 79.4°F 55.5°F 0.34 in 79.0°F 54.3°F 0.38 in
June 82.5°F 58.7°F 0.04 in 86.3°F 59.0°F 0.11 in
July 88.1°F 61.9°F 0.09 in 91.4°F 60.6°F 0.00 in
August 90.2°F 62.2°F 0.01 in 90.2°F 60.3°F 0.02 in
September 88.8°F 61.7°F 0.10 in 86.7°F 58.7°F 0.06 in
October 84.3°F 57.8°F 0.62 in 77.5°F 54.2°F 0.42 in
November 75.6°F 52.5°F 0.83 in 64.6°F 46.2°F 1.18 in
December 67.8°F 47.6°F 2.34 in 55.8°F 40.4°F 2.53 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 →