ERA5 almanac comparison — 8 years of real data
Hilton Head vs Mérida: weather in May
Mérida edges out Hilton Head for sun in May: 47% clear historically versus 39% (8-year ERA5 average, a 8-point gap). Hilton Head also sees measurably more rain than Mérida this month (39% vs 19% of days). Both are viable — Mérida is the safer bet.
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.
Hilton Head
SC
- Clear days, May
- 39%
- Sample size
- n=248 days
- Avg high
- 81°F
- Early May (1st–15th)
- 44%
- Late May (16th–end)
- 35%
- Rain frequency
- 39% of days
Mérida
MX
- Clear days, May
- 47%
- Sample size
- n=248 days
- Avg high
- 97°F
- Early May (1st–15th)
- 62%
- Late May (16th–end)
- 33%
- Rain frequency
- 19% of days
Compare Hilton Head vs Mérida 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.