Thousands of people have flocked to south east Queensland beaches in an attempt to get some relief from the heat, despite the majority of beaches remaining closed.

Beaches across the Gold and Sunshine Coasts have been closed by life savers, concerned strong swells and high tides will prove too dangerous a mix for swimmers.

Noosa main beach and a small section of Mudjimba beach are the only open areas on the Sunshine Coast, while swimmers are trying their luck at the protected estuaries at Currumbin and Tallebudgera on the Gold Coast.

Weatherzone meteorologist Josh Fischer said an intense low was responsible for the on-shore conditions, with sea heights reaching over two metres and swells hitting the four metre mark.

Sunshine Coast Surf Life Saving duty officer Kevin Lynch said thousands of beach goers lined about a 1.5km stretch of beach at Mooloolaba and despite both visual and verbal warnings, people were still trying their luck in the water.