ERA5 almanac comparison — 8 years of real data
San Luis Obispo vs Vail: weather in January
San Luis Obispo edges out Vail for sun in January: 11% clear historically versus 0% (8-year ERA5 average, a 11-point gap). Vail also sees measurably more rain than San Luis Obispo this month (38% vs 19% of days). Both are viable — San Luis Obispo is the safer bet.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific January. For this
week’s actual forecast, each destination links to its live page below.
San Luis Obispo
CA
- Clear days, January
- 11%
- Sample size
- n=248 days
- Avg high
- 64°F
- Early January (1st–15th)
- 8%
- Late January (16th–end)
- 14%
- Rain frequency
- 19% of days
Vail
CO
- Clear days, January
- 0%
- Sample size
- n=248 days
- Avg high
- 30°F
- Early January (1st–15th)
- 0%
- Late January (16th–end)
- 0%
- Rain frequency
- 38% of days
Compare San Luis Obispo vs Vail 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.