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SunnyDays

ERA5 almanac comparison — 8 years of real data

30A / Seaside vs Sea Island: weather in September

Essentially a tie in September: 30A / Seaside is 32% clear historically, Sea Island is 32% clear (8-year ERA5 average) — within the noise. Avg high 85°F vs 83°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 September. For the actual forecast right now, each destination links to its live page below.

30A / Seaside

FL

Clear days, September
32%
Sample size
n=240 days
Avg high
85°F
Early September (1st–15th)
27%
Late September (16th–end)
37%
Rain frequency
48% of days
See the live forecast →

Sea Island

GA

Clear days, September
32%
Sample size
n=240 days
Avg high
83°F
Early September (1st–15th)
26%
Late September (16th–end)
37%
Rain frequency
53% of days
See the live forecast →

Frequently asked

Is 30A / Seaside or Sea Island warmer in September?

30A / Seaside runs warmer by day in September. 30A / Seaside averages highs of 85°F (highs n=240 days); Sea Island averages highs of 83°F (highs n=240 days) (ERA5 2018–2025). Historical averages, not a forecast.

Does it rain more in 30A / Seaside or Sea Island in September?

Days with measurable rain: 30A / Seaside 48%, Sea Island 53% (n=240 and n=240 days). ERA5 2018–2025; historical, not a forecast.

Which is sunnier in September, 30A / Seaside or Sea Island?

Essentially a tie in September: 30A / Seaside is 32% clear historically, Sea Island is 32% clear (8-year ERA5 average) — within the noise. Avg high 85°F vs 83°F. Pick based on flight time or price, not weather — the weather won't decide this one for you.

Compare 30A / Seaside 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 forecast for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.