ERA5 almanac comparison — 8 years of real data
Atlanta vs Hilton Head: weather in September
Atlanta edges out Hilton Head for sun in September: 40% clear historically versus 33% (8-year ERA5 average, a 7-point gap). Hilton Head also sees measurably more rain than Atlanta this month (50% vs 34% of days). Both are viable — Atlanta is the safer bet.
Atlanta
GA
- Clear days, September
- 40%
- Sample size
- n=240 days
- Avg high
- 83°F
- Early September (1st–15th)
- 38%
- Late September (16th–end)
- 42%
- Rain frequency
- 34% of days
Hilton Head
SC
- Clear days, September
- 33%
- Sample size
- n=240 days
- Avg high
- 83°F
- Early September (1st–15th)
- 28%
- Late September (16th–end)
- 38%
- Rain frequency
- 50% of days
Frequently asked
Is Atlanta or Hilton Head warmer in September?
Equally warm by day in September. Atlanta averages highs of 83°F (highs n=240 days); Hilton Head averages highs of 83°F (highs n=240 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Atlanta or Hilton Head in September?
Hilton Head is measurably wetter than Atlanta. Days with measurable rain: Atlanta 34%, Hilton Head 50% (n=240 and n=240 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in September, Atlanta or Hilton Head?
Atlanta edges out Hilton Head for sun in September: 40% clear historically versus 33% (8-year ERA5 average, a 7-point gap). Hilton Head also sees measurably more rain than Atlanta this month (50% vs 34% of days). Both are viable — Atlanta is the safer bet.
Compare Atlanta vs Hilton Head 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.