Hilton Head Island weather in August
August in Hilton Head Island: sweltering, soaked, with muggy air — fine if you can take 13 rainy days.
Updated September 2026 · climate normals from ERA5 reanalysis
#7 of 12 months in Hilton Head Island · #792 of 1413 destinations to visit in August · comfort 76/100 (tier B)
- Days
- 31°C
- Nights
- 25°C
- Wet days
- 13
- Sun
- 10.7 h
- Humidity
- 82%
- Daylight
- 13 h

Traveller notes on Hilton Head Island in August
Other months in Hilton Head Island
Regulars are specific it's genuinely the humidity more than the raw heat that makes this month tough, though a steady breeze helps take the edge off, evening thunder showers a near-daily feature that typically clear within 10 to 30 minutes rather than settling in. Our row backs that hot, genuinely wet read, 32.2C reading as a scorching 37C, over 25.3C nights feeling 30C, with a substantial 203.4mm of rain across 10.5 days and humidity at 79 percent. Regulars are consistent both the very start and the later weeks of the month run noticeably more crowded, a quieter mid-month stretch the practical workaround for anyone avoiding peak traffic. The sea sits at a bath-warm 30.4C. The record: 11.9 hours of sun, an 18.7 kph wind and AQI 68.
Regulars call this a genuinely nice month - hot, but not July or August hot, with a steady ocean breeze regulars credit for keeping the beach comfortable even as humidity builds through the month. Our row backs the heat, 30.5C reading as 35C at 78.3 percent humidity, over 23.5C nights, with 139.9mm of rain across 9.6 days. The sea is refreshingly cool rather than warm at 26C, murky enough that stingrays are only visible in the shallowest water. Gnats are the one insect regulars flag as temperature-triggered rather than seasonal outright - worst in the low seventies Fahrenheit, so a cooler June week can bring them out where a hotter one keeps them away. Beaches stay noticeably less crowded than July. The record: 11.5 hours of sun, a 19.8 kph wind and AQI 54.
Asked whether hurricane season should put them off September, regulars answer with geography and lead time rather than reassurance: the island sits in an unlikely spot for a direct landfall, and a storm that does threaten gives several days of warning, so the decision can be made late. What they sell the month on is the emptiness - the summer crowds have gone, the water is still warm at 28.2C, and the temperatures are comfortable at 29.4C over 22.8C. They are also honest that September is among the wettest months, quoting about five inches; our row has 157.2mm falling across just 7.1 days, twenty-two millimetres each. The record: humidity 79 percent, 9.9 hours of sun and a 19.8 kph wind.
October is the month locals name for Hilton Head, and their figure - an average high of 76F, usually in the 70s and sometimes the 80s - sits just under our row's 25.7C. The water is the part that changes through the month: still warm enough to swim in early October, down to the high 60s Fahrenheit by the end, with our 22.7C the average of the two. Everything else about the month is quieter. The children are back at school, so the crowd turns to golf and tennis, and rates and rentals are discounted. On hurricanes they are matter-of-fact: this is officially the last month of the season, and residents point out the island has not had one in over a century and has evacuated twice in thirty years. The record: 18.2C nights, 77.8mm across just 4.8 precipitation days, 9.1 hours of sun and AQI 41.
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Hilton Head Island climate normals — August
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Hilton Head Island in August
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.
Peak crowdsSchool-holiday season, Summer break in United States, school holidays in 2 of the markets that fill it(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 August
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 ↗
- Season
School-holiday season
5 Jun – 20 AugSchool holidaysCrowdedBook earlyThe island runs on the school calendar: bike paths busy by nine, beach clubs full, and rentals let by the week from Saturday to Saturday, which is why every road on and off jams on the same morning.
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 August — FAQ
- Is August a good time to visit Hilton Head Island?
- August in Hilton Head Island: sweltering, soaked, with muggy air — fine if you can take 13 rainy days. It ranks #7 of 12 months for Hilton Head Island on SeasonMap's comfort score (76/100).
- What is the weather like in Hilton Head Island in August?
- In August, Hilton Head Island averages a daily high of 31.3°C and a low of 25.1°C, with about 195.1 mm of rain over roughly 12.7 rainy days.
- What is the air quality in Hilton Head Island in August?
- Hilton Head Island has a mean US Air Quality Index of about 57 in August.
Within 300 km: Jacksonville's Loggerhead nesting on 1 May – 31 Oct, and Myrtle Beach's Loggerhead nesting on 1 May – 31 Oct.