ERA5 almanac comparison — 8 years of real data
Jamaica vs Key West: weather in May
Key West is the clear winner for sun in May: 33% of days historically clear versus just 3% in Jamaica — a 30-point gap across 8 years of ERA5 data. Jamaica also sees measurably more rain than Key West this month (78% vs 38% 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 May. For this
week’s actual forecast, each destination links to its live page below.
Jamaica
JM
- Clear days, May
- 3%
- Sample size
- n=248 days
- Avg high
- 86°F
- Early May (1st–15th)
- 4%
- Late May (16th–end)
- 3%
- Rain frequency
- 78% of days
Key West
FL
- Clear days, May
- 33%
- Sample size
- n=248 days
- Avg high
- 82°F
- Early May (1st–15th)
- 38%
- Late May (16th–end)
- 29%
- Rain frequency
- 38% of days
Compare Jamaica vs Key West 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.