ERA5 almanac comparison — 8 years of real data
Boston vs St. Martin: weather in November
St. Martin edges out Boston for sun in November: 17% clear historically versus 2% (8-year ERA5 average, a 15-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 November. For this
week’s actual forecast, each destination links to its live page below.
Boston
MA
- Clear days, November
- 2%
- Sample size
- n=240 days
- Avg high
- 51°F
- Early November (1st–15th)
- 5%
- Late November (16th–end)
- 0%
St. Martin
SX
- Clear days, November
- 17%
- Sample size
- n=240 days
- Avg high
- 78°F
- Early November (1st–15th)
- 13%
- Late November (16th–end)
- 21%
Compare Boston 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.