ERA5 almanac comparison — 8 years of real data
Costa Rica — Guanacaste vs Savannah: weather in October
Savannah is the clear winner for sun in October: 47% of days historically clear versus just 2% in Costa Rica — Guanacaste — a 45-point gap across 8 years of ERA5 data. Costa Rica — Guanacaste also sees measurably more rain than Savannah this month (95% vs 24% of days). This isn't close.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific October. For this
week’s actual forecast, each destination links to its live page below.
Costa Rica — Guanacaste
CR
- Clear days, October
- 2%
- Sample size
- n=248 days
- Avg high
- 86°F
- Early October (1st–15th)
- 0%
- Late October (16th–end)
- 3%
- Rain frequency
- 95% of days
Savannah
GA
- Clear days, October
- 47%
- Sample size
- n=248 days
- Avg high
- 78°F
- Early October (1st–15th)
- 48%
- Late October (16th–end)
- 47%
- Rain frequency
- 24% of days
Compare Costa Rica — Guanacaste vs Savannah 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.