The Joint Australian Tsunami Warning Centre has issued a tsunami warning for the Illawarra and the entire NSW coastline following an underwater volcanic eruption near Tonga.
In issuing the marine threat warning, the centre - operated by the Bureau of Meteorology (BOM) and Geoscience Australia - says dangerous rips, waves, strong ocean currents and localised overflow onto the immediate foreshore are possible for several hours from 8.45pm.
There is no threat of land inundation, but people are advised to move away from the water's edge along beaches, marinas, coastal estuaries, harbours, and rock platforms.
"While evacuations are not necessary for marine warning zones, people in these areas are advised to leave the water and move away from the immediate water's edge," the BOM said in a statement on Saturday night.
They also said tsunami waves were more powerful than the same size beach waves.
"There will be many waves and the first wave may not be the largest."
Boats in harbours, estuaries or shallow coastal water should return to shore, while vessels already at sea should stay offshore in water at least 25 metres deep.
People are urged not to go to the beach because of the risk of dangerous, localised flooding.
The Bureau said the Hunga Tonga-Hunga Ha'apai volcano erupted at 3.10pm AEDT on Saturday, and tsunami waves have been observed as a result of the eruption.
The BOM said a tsunami wave height of 1.27m was observed on Norfolk Island at 9pm AEDT and an 82cm wave was registered on the Gold Coast at 10.54pm AEDT on Saturday.
The SES has ordered the evacuation of low-lying parts of Lord Howe Island and people on Norfolk Island are being urged to evacuate to higher ground due to the threat of major land inundation.
NSW Police Force, Marine Area Command advise:
- People should consider staying out of the water and avoid walking near surf-exposed areas.
- Rock fishers should avoid coastal rock platforms exposed to the ocean and seek a safe location that is sheltered from the surf.
- Boaters planning to cross shallow water and ocean bars should consider changing or delaying their voyage.
- Boaters already on the water should carry the appropriate safety equipment and wear a lifejacket.
- Boaters should remember to log on with their local Marine Rescue radio base, via VHF Radio or the Marine Rescue APP, and consider their safety management plan.
For latest and further information on tsunami warnings, please call 1300 TSUNAMI(1300 878 626) or visit www.bom.gov.au/tsunami
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