A police officer in Whangarei says more publicity about the dangers of king tides may be needed to prevent drownings like Sunday's fatality in Northland.
Fiona Eileen Gooder, 43, who helped save her two children from wild surf at Ruakaka, near Marsden Point, was dragged from the water unconscious and could not be revived.
Sergeant Dave Hamilton was in the patrolled area of the beach and said the surf was huge and there was a strong rip.
He said people can underestimate the power of king tides, and it might be wise to warn the public before the next one due at this time next year.
Meanwhile, scientists are warning New Zealanders to get used to the higher-than-normal tides because they will be happening every fortnight by 2060.
A number of king tides have been recorded since Friday including at Auckland's Waitemata Harbour. They typically occur every seven months and continue for several days, and can be forecast up to a week in advance.
Rob Bell from the National Institute of Water and Atmospheric Research (NIWA) says in a few decades king tides will happen often as a result of climate change, because the water level becomes higher as the sea level rises.
Dr Bell says people need to be aware king tides are a danger, and should stay away from the water at high tide.