The forecast path of Cyclone Pam. Photo / MetService
A once-in-20-year cyclone is threatening the Bay and residents are being warned to prepare for wild weather.
Weatherwatch forecaster Philip Duncan said tropical Cyclone Pam looked likely to be the biggest storm to hit the area since Cyclones Fergus and Drena in 1996 and 1997.
"Once in 10 to 20 years do you see a low of this magnitude coming down this close to us or hitting us," he said.
The storm was heading towards Vanuatu last night and Mr Duncan said it was still too early to accurately predict exactly how close it would come but the east coast was definitely in for a wet and windy weekend with huge swells expected.
Last night Mr Duncan told the Bay of Plenty Times the eye of the storm did not look likely to make landfall but that did not mean there would not be damage. The worst of the weather was expected to hit the Western Bay on Sunday night and Monday morning, he said.
"There will be rain in the area pushing in towards the northern parts of the Bay of Plenty up towards the Coromandel. Monday will be a windy day and it will clear the skies up."
The swell along the Mount Maunganui and Papamoa coastline would be picking up across the weekend, he said.
"By the time Monday arrives there will be some very big swells coming through. We're looking at 3m swells. Especially on the eastern side it could be 3m to 4m. The very top of East Cape, they could be 6m swells."
While the seas would drop back during the day on Monday Mr Duncan said people should be wary on Tuesday as strong rips and currents were likely to have formed.
"This is a very dangerous storm. There could be things that happen that you're not normally used to at the beach. Avoid being in the water Monday, Tuesday and probably Sunday too," he said. "The swells will be massive. There is a high chance of coastal erosion, particularly on Sunday night and Monday morning."
MetService forecaster Georgina Griffiths said tropical Cyclone Pam was expected to intensify to a category 5 storm, the most severe, by 7am this morning and be positioned to the east of northern Vanuatu.
"Once it moves south into the New Zealand region, it is likely to revert back to a Category 4 system," she said.
Category 4 storms have winds between 157km/h and 198km/h.
"At this stage, the eastern seaboard of the North Island could possibly get the full trifecta of impacts - damaging seas along the eastern coastline, gale to severe gale SE winds, and the possibility of heavy rain," Ms Griffiths said.
Mount Maunganui Lifeguard Service general manager Glenn Bradley was "urging all beach goers to exercise real caution this weekend and particularly early next week if this storm progresses as currently forecast".
"It does look like it's going to be solid and very, very strong surf during the weekend and really big, what we'd call severe, conditions on Monday."
Mr Bradley said it was important people were cautious and "if in doubt, stay out".
"It's about the sort of stuff where there's about a dozen surfers in the country that should be surfing exposed coasts. Serious big wave surfers only," he said.
"At this stage it certainly looks like it could be the most significant swell or surf event we've had here in the last five to 10 years."
Experienced surfer Andy Jordan was looking forward to the big surf on Monday but expected the best waves would be found further afield than the Mount Maunganui and Papamoa coast. "Probably Monday will be huge," he said. "We'll definitely be closing the factory to go and look for some waves."
Mr Jordan, who has been surfing daily for more than 30 years, said the conditions were only suitable for very experienced surfers.
"There should be some challenging waves, definitely. It will be pretty dangerous ..."
Civil Defence emergency management regional manager Clinton Naude said people needed to prepare before the storm hit. "Get your gutters sorted, check any drains, make sure your outdoor furniture is secure."
Trampolines, and rubbish bins also needed to be tied down and boat owners needed to check their moorings, he said.
Mr Naude said people should also check their emergency survival kits and make sure they had torches and batteries in case high winds caused power outages and make sure they have food and water for three days.
Tauranga City Council also issued instructions for contractors to check almost 100 sites around the city known to cause problems in severe weather. There would also be contractors on call during the weekend.
What to do when a warning is issued and during a storm
•Stay informed on weather updates.
•Secure, or move indoors, all items that could get blown about and cause harm in strong winds.
•Close windows, external and internal doors. Pull curtains and drapes over unprotected glass areas to prevent injury from shattered or flying glass.
•If the wind becomes destructive, stay away from doors and windows and shelter further inside the house.
•Water supplies can be affected so it is a good idea to store drinking water in containers and fill bathtubs and sinks with water.
•Don't walk around outside and avoid driving unless absolutely necessary.
•Power cuts are possible in severe weather. Unplug small appliances which may be affected by electrical power surges. If power is lost unplug major appliances to reduce the power surge and possible damage when power is restored.
•Bring pets inside. Move stock to shelter. If you have to evacuate, take your pets with you.
- Civil Defence
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