The highest day temperature in July 2025 was 98°F. The lowest night temperature was 79°F. The average values for day and night temperatures during July were 90.1°F и 83.5°F respectivly.

The average sea surface temperature in July 2025 for Hilton Head Island was 89.7°F. The maximum and minimum values were 87.6°F and 92.6°F respectively.

Most of the days in July are cloudy but you can also expect sunny or gloomy days.

Precipitation total in July for Hilton Head Island is 1.9 in. It makes july one of the most rainy months of the year.

The average wind speed in July is 7.0 mph. This value is relatively stable throughout the year.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Hilton Head Island in July is 7.6 hours.