ERA5 almanac comparison — 8 years of real data
Lisbon vs Santorini: weather in August
Essentially a tie in August: Lisbon is 91% clear historically, Santorini is 93% clear (8-year ERA5 average) — within the noise. Avg high 84°F vs 85°F. Pick based on flight time or price, not weather — the weather won't decide this one for you.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific August. For this
week’s actual forecast, each destination links to its live page below.
Lisbon
PT
- Clear days, August
- 91%
- Sample size
- n=248 days
- Avg high
- 84°F
- Early August (1st–15th)
- 93%
- Late August (16th–end)
- 90%
Santorini
GR
- Clear days, August
- 93%
- Sample size
- n=248 days
- Avg high
- 85°F
- Early August (1st–15th)
- 96%
- Late August (16th–end)
- 90%
Compare Lisbon vs Santorini 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.