ERA5 almanac comparison — 8 years of real data
Nantucket vs St. Martin: weather in March
St. Martin edges out Nantucket for sun in March: 28% clear historically versus 0% (8-year ERA5 average, a 28-point gap). Both are viable — St. Martin is the safer bet.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific March. For this
week’s actual forecast, each destination links to its live page below.
Nantucket
MA
- Clear days, March
- 0%
- Sample size
- n=248 days
- Avg high
- 43°F
- Early March (1st–15th)
- 0%
- Late March (16th–end)
- 0%
St. Martin
SX
- Clear days, March
- 28%
- Sample size
- n=248 days
- Avg high
- 75°F
- Early March (1st–15th)
- 34%
- Late March (16th–end)
- 23%
Compare Nantucket vs St. Martin 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.