Climate twins of San Diego, CA
These are the US cities whose 12-month climate pattern most closely matches San Diego'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 Diego vs its climate twin
Top match: Santa Clara, CA
| Month | San Diego | Santa Clara | ||||
|---|---|---|---|---|---|---|
| High | Low | Precip | High | Low | Precip | |
| January | 67.3°F | 46.0°F | 2.32 in | 59.8°F | 41.8°F | 2.80 in |
| February | 67.3°F | 46.9°F | 2.65 in | 62.4°F | 43.9°F | 2.69 in |
| March | 68.5°F | 49.6°F | 1.63 in | 65.9°F | 46.3°F | 2.08 in |
| April | 70.7°F | 52.4°F | 0.77 in | 69.2°F | 48.4°F | 1.07 in |
| May | 72.1°F | 56.6°F | 0.28 in | 73.8°F | 52.1°F | 0.39 in |
| June | 74.7°F | 60.0°F | 0.06 in | 79.1°F | 55.5°F | 0.18 in |
| July | 79.8°F | 64.0°F | 0.07 in | 80.8°F | 58.1°F | 0.00 in |
| August | 82.0°F | 65.3°F | 0.01 in | 81.4°F | 58.6°F | 0.05 in |
| September | 81.4°F | 63.6°F | 0.17 in | 80.7°F | 57.2°F | 0.07 in |
| October | 77.8°F | 57.8°F | 0.54 in | 75.8°F | 52.7°F | 0.53 in |
| November | 72.7°F | 50.1°F | 0.91 in | 66.1°F | 45.7°F | 1.33 in |
| December | 67.3°F | 45.3°F | 1.61 in | 59.5°F | 41.7°F | 2.29 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 →