ERA5 almanac comparison — 8 years of real data
Charleston vs Sea Island: weather in April
Essentially a tie in April: Charleston is 38% clear historically, Sea Island is 36% clear (8-year ERA5 average) — within the noise. Avg high 74°F vs 74°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 April. For this
week’s actual forecast, each destination links to its live page below.
Charleston
SC
- Clear days, April
- 38%
- Sample size
- n=240 days
- Avg high
- 74°F
- Early April (1st–15th)
- 30%
- Late April (16th–end)
- 45%
- Rain frequency
- 26% of days
Sea Island
GA
- Clear days, April
- 36%
- Sample size
- n=240 days
- Avg high
- 74°F
- Early April (1st–15th)
- 24%
- Late April (16th–end)
- 49%
- Rain frequency
- 28% of days
Compare Charleston vs Sea Island 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.