Tropical Cyclone Tino: Beachgoing Kiwis alerted to potentially 'deadly' seas as storm throttles Pacific

Parts of New Zealand will be exposed to "dangerous beach conditions" over the coming days as a massive offshore storm potentially leads to gigantic waves and strong rips, WeatherWatch says.

Tropical Cyclone Tino is storming its way across the Pacific and is currently sitting south of Fiji's western Rotuma Island with gusts reaching 100km/h. That's prompted evacuation centres to be opened in northern Fiji as it heads towards Vanua Levu. Preparations are also underway in Tonga for the storm to strike.

While Tino may be hundreds of kilometres away, WeatherWatch says New Zealand isn't safe from its wrath as there may be massive seas in its aftermath, affecting eastern North Island beaches from late Sunday until late on Wednesday. It has also prompted warnings from Surf Life Saving New Zealand.

WeatherWatch head forecaster Philip Duncan explains that by late in the weekend, Tropical Cyclone Tino will become an ex-cyclone. Despite that, the storm's remnants will "rapidly intensify" as the cyclone leaves the tropics and heads south into cooler waters.

"In this case we expect the remnants of Tino to really grow and intensify well to NZ's east into a much larger extra tropical low."

That is what may cause "dangerous beach conditions" for Kiwis on eastern beaches.

"We've seen set ups like this before where the weather over your favourite beach is sunny, hot and calm, but the local weather is masking the dangers at sea," said Duncan.

"These giant offshore ex-cyclones have proven deadly in recent history by creating sudden large random waves, extra strong rips and currents that can turn safe beaches into dangerous ones - but there may be no hint of this with the local weather.

"The storm should be just far enough east to reduce the risks of serious coastal erosion."

Surf Life Saving says beachgoers should be "extra vigilant" on the east coast due to the potential conditions created by the ex-tropical cyclone.

"We often experience an increase in difficult, challenging rescues during this type of weather pattern," said national lifesaving manager Allan Mundy.

"Do not swim alone and stay well within your depth. Be aware that when a large surging wave comes into shore, what was your swimming depth will be lost as the surge carries you out at least an extra metre – that’s half the height of an adult!"

As well as swimming between the flags, Mundy wants the public to remember the 3Rs Rip Survival Plan.

"Relax and float to conserve your energy. Raise your hand to signal for help. Ride the rip until it stops and you can swim back to shore or help arrives."

Tropical Cyclone Tino: Beachgoing Kiwis alerted to potentially 'deadly' seas as storm throttles Pacific
Photo credit: Surf Life Saving.

"With Surf Lifeguards doing observational patrols in the area, either we will see you or someone will alert us to your need," Mundy said.

He also wants people walking on shore to be aware of large waves surging up the beach.

"These have the power to knock people over and will travel well past the high tide mark. Young children, the elderly and small dogs are most at risk."

So, while Tino itself may have no "direct threat" to New Zealand and beachgoing Kiwis should expect "hot, sunny and settled" local weather, the Tropical Cyclone's aftermath could be something to watch for.