Hilton Head Islander MacKenzie Johnston, 17, begins a backflip as he flies off of his skimboard at Coligny Beach Park on Monday afternoon. Johnston and several of his friends were were using a Banshee Bungee -- elastic cord anchored in the sand just offshore -- to launch themselves out into the ocean. The slingshot effect of the cord allows users to get farther out and to reach larger waves than they can by running into the surf.
A heat advisory will be in effect for Beaufort County from noon until 8 p.m. today, according to the National Weather Service in Charleston.
A sea breeze bringing more humid air is expected to move inland across coastal counties, according to the weather service.
The added humidity combined with high temperatures will produce heat indexes of 112 to 116 degrees for brief periods, according to the statement.