SeasonMapHilton Head Island weather in September
United States
September in Hilton Head Island: hot, soaked, with clean air — fine if you can take 7 rainy days.
#4 of 12 months in Hilton Head Island · #521 of 1383 destinations to visit in September · comfort 84/100 (tier A)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on Hilton Head Island in September
Other months in Hilton Head Island
Hilton Head's forum calls late May the sweet spot — warm enough for the beach and pool, genuinely rare to get as hot as July or August, roughly one day in four or five bringing rain, usually late afternoon or evening. Regulars note the ocean is swimmable but not warm, and that May stays noticeably quieter than the June-through-August rush since most schools are still in session.
Add your own note from Hilton Head Island's card on the map.
Hilton Head Island climate normals — September
| Daytime high | 29°C / 85°F | 🥵 hot |
|---|---|---|
| Nighttime low | 23°C / 73°F | |
| Feels like (high) | 32°C / 90°F | |
| Sea temperature | 28°C / 83°F | ♨️ bath-warm |
| Rainfall | 157 mm / 6.2 in | ⛈ soaked |
| Rainy days | 7 days | |
| Humidity | 79% | 💦 very humid |
| Dew point | 22°C / 71°F | |
| Sunshine | 9.9 h/day | |
| Daylight | 12.3 h | |
| Wind | 20 km/h / 12 mph | |
| Air quality (US AQI) | 46 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Hilton Head Island in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
BusySummer break in United States(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Hilton Head Island's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherHilton Head Island's best weather comes in April, May and October — separate windows, not one continuous season.
Best weatherFair weatherToughest weather
What's on in Hilton Head Island in September
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Nature
Loggerhead nesting
1 May – 31 OctTurtle nestingA couple of hundred loggerhead nests a season, laid from May and hatching through October. A volunteer patrol walks the twelve miles of beach at first light marking the new ones.
- Rule
Beachfront lights-out rule
1 May – 31 OctAny light visible from the sand has to be shielded or off between 10pm and 6am through nesting season, which is why oceanfront rentals come with blackout blinds and no torches on the beach after dark. Source ↗
- Season
Sea warm enough
1 Jun – 10 Oct · usuallyThe Atlantic here is swimmable from June and stays that way well past Labor Day. What changes in early autumn is the number of people on the sand, not the water.
- Hazard
Atlantic hurricane season
1 Jun – 30 NovDirect hits on this stretch of the South Carolina coast are rare, but the island is flat, low and reached by one causeway, so evacuation orders come early and often. September is the month that matters. Source ↗
Nearby, and something's on
Within 300 km of Hilton Head Island — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Hilton Head Island?
Hilton Head Island in September — FAQ
- Is September a good time to visit Hilton Head Island?
- September in Hilton Head Island: hot, soaked, with clean air — fine if you can take 7 rainy days. It ranks #4 of 12 months for Hilton Head Island on SeasonMap's comfort score (84/100).
- What is the weather like in Hilton Head Island in September?
- In September, Hilton Head Island averages a daily high of 29.4°C and a low of 22.8°C, with about 157.2 mm of rain over roughly 7.1 rainy days.
- What is the air quality in Hilton Head Island in September?
- Hilton Head Island has a mean US Air Quality Index of about 46 in September.
Other months in Hilton Head Island
Compare Hilton Head Island in September
Warmer or cooler than Hilton Head Island in September
Similar destinations in North America — September
Within 300 km: Jacksonville's Loggerhead nesting on 1 May – 31 Oct, and Myrtle Beach's Loggerhead nesting on 1 May – 31 Oct.