Queensland

Queensland runs the longest stretch of the Australian east coast, from the New South Wales border up the Gold Coast and Sunshine Coast past Brisbane and on through the Great Barrier Reef to the Torres Strait. The tide signature varies a lot across that range. The southern Queensland open coast — Gold Coast, Sunshine Coast, Brisbane River mouth — runs a modest semidiurnal swing close to the New South Wales pattern: mean range at the Gold Coast Seaway about 1.3 metres, climbing toward 1.8 on spring tides. Further north along the reef coast the geometry of the lagoon between the reef and the mainland amplifies the signal: Townsville and Mackay run mean ranges close to 3 metres. The Gold Coast Seaway runs hard on the change of tide, with currents through the rock-walled entrance exceeding three knots — slack water is the right window for crossings. The wide open beaches at Surfers Paradise and Burleigh widen by 10–15 metres at low water. The Australian Bureau of Meteorology and Maritime Safety Queensland publish the authoritative tide tables.