ERA5 almanac comparison — 8 years of real data
Big Sur vs Gulf Shores: weather in September
Essentially a tie in September: Big Sur is 35% clear historically, Gulf Shores is 32% clear (8-year ERA5 average) — within the noise. Avg high 72°F vs 85°F. Gulf Shores also sees measurably more rain than Big Sur this month (42% vs 4% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Big Sur
CA
- Clear days, September
- 35%
- Sample size
- n=240 days
- Avg high
- 72°F
- Early September (1st–15th)
- 40%
- Late September (16th–end)
- 30%
- Rain frequency
- 4% of days
Gulf Shores
AL
- Clear days, September
- 32%
- Sample size
- n=240 days
- Avg high
- 85°F
- Early September (1st–15th)
- 31%
- Late September (16th–end)
- 33%
- Rain frequency
- 42% of days
Frequently asked
Is Big Sur or Gulf Shores warmer in September?
Gulf Shores runs warmer by day in September. Big Sur averages highs of 72°F (highs n=240 days); Gulf Shores averages highs of 85°F (highs n=240 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Big Sur or Gulf Shores in September?
Gulf Shores is measurably wetter than Big Sur. Days with measurable rain: Big Sur 4%, Gulf Shores 42% (n=240 and n=240 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in September, Big Sur or Gulf Shores?
Essentially a tie in September: Big Sur is 35% clear historically, Gulf Shores is 32% clear (8-year ERA5 average) — within the noise. Avg high 72°F vs 85°F. Gulf Shores also sees measurably more rain than Big Sur this month (42% vs 4% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Compare Big Sur vs Gulf Shores 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.