ERA5 almanac comparison — 8 years of real data
Mazatlán vs San Diego: weather in October
Essentially a tie in October: Mazatlán is 58% clear historically, San Diego is 60% clear (8-year ERA5 average) — within the noise. Avg high 86°F vs 75°F. Mazatlán also sees measurably more rain than San Diego this month (27% vs 7% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Mazatlán
MX
- Clear days, October
- 58%
- Sample size
- n=248 days
- Avg high
- 86°F
- Early October (1st–15th)
- 49%
- Late October (16th–end)
- 67%
- Rain frequency
- 27% of days
San Diego
CA
- Clear days, October
- 60%
- Sample size
- n=248 days
- Avg high
- 75°F
- Early October (1st–15th)
- 62%
- Late October (16th–end)
- 59%
- Rain frequency
- 7% of days
Compare Mazatlán vs San Diego in another month
All percentages are historical averages from the ERA5 reanalysis via Open-Meteo, 8 full years (2018–2025). “Clear” means avg high ≥ 72 °F, precipitation < 1 mm, and a non-precipitation weather code. This is history, not a forecast. The live 7-day outlook for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.