ERA5 almanac comparison — 8 years of real data
Athens vs Ibiza: weather in September
Athens edges out Ibiza for sun in September: 72% clear historically versus 54% (8-year ERA5 average, a 18-point gap). Both are viable — Athens is the safer bet.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific September. For this
week’s actual forecast, each destination links to its live page below.
Athens
GR
- Clear days, September
- 72%
- Sample size
- n=240 days
- Avg high
- 84°F
- Early September (1st–15th)
- 72%
- Late September (16th–end)
- 72%
Ibiza
ES
- Clear days, September
- 54%
- Sample size
- n=240 days
- Avg high
- 82°F
- Early September (1st–15th)
- 56%
- Late September (16th–end)
- 53%
Compare Athens vs Ibiza 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.