Tonga's northern islands are bracing for the arrival of a powerful tropical cyclone which is forecast to bring hurricane force winds.
Tropical Cyclone Ian is currently packing average winds of 100 kilometres per hour with gusts of up to 140 kilometres per hour.
It's currently a Category Four system located about 300 kilometres north west of Vava'u and is moving south east at about five kilometres per hour.
Ian is expected to remain a Category Four storm for the next 24 hours and then weaken before leaving Tonga late Sunday.
Forecaster Shalwin Singh from the Fiji Meteorological Service says Tonga's northern islands will feel the brunt of Ian's fury.
"As the storm tracks south eastwards, we expect the Vava'u Group and the Ha'apai Group to be the worst affected, they will encounter the severe hurricane force winds," he said.
"It is a severe tropical cyclone now and close to its centre we expect the average winds to be up to 90 knots and that is quite significant.
"We expect hurricane force winds - that is above 65 knots - to be within 20 nautical miles of the centre.
Ian is expected to brush below Niuafo'ou, Tonga's most northerly island, in the Niua group.
Mr Singh says the capital Nuku'alofa is not directly in Ian's path but may experience heavy rains and possible flooding.
Leveni Aho is the Director of Tonga's National Emergency Management Office and says residents of the northern islands should prepare for the worst.
"The potential and the threat now lies in the islands of Vava'u and Ha'apai in the next 12 to 34 hours," he said.
"We have been in contact with our northern islands, the weather still there is pretty calm but we expect that it will escalate."
The key administrative island of Vava'u and its capital Neiafu - Tonga's second largest town - shares the same name as its group, while Lifuka island and its regional capital Pangai is the administrative centre of the Ha'apai group.
Destructive winds are likely to begin several hours before the cyclone's centre passes overhead or nearby Vava'u in the next 18-24 hours, and across Ha'apai on Friday afternoon local time.
Heavy rain, the flooding of low lying areas and very rough seas are also expected.
A forecaster from the Fiji Meteorological Service, Sanjay Prakash, told Radio Australia's the cyclone will be "catastrophic" and "bring a lot of damage to the kingdom".
"It will be at its peak during the time of landfall," he said.
Mr Aho is urging affected residents to make sure they are well prepared.
"A reminder to people to make sure that they have enough supplies for the next 72 hours in terms of water, drinking water, and food and (ensure) some basic necessities like radios and mobile phones are charged to maintain communication," he said.
"Make sure that they are in a safe place, if ever the winds arrive keeping away from low lying areas and the coastal areas, make sure that they are in a safe house, sheltered."
Earlier this week, a cyclone alert was issued for the island groups of Vava'u and Ha'apai with warnings of gale force winds, heavy rain, squally thunderstorms and the risk of sea flooding.
The alert was cancelled early on Tuesday, but both the Fiji Meteorological Service and the Tonga Meteorological Service re-issued warnings on Wednesday.
Ian has been hovering in the ocean between Fiji and Tonga since Monday.
People in Tonga's Vava'u islands have begun boarding up windows in preparation for Cyclone Ian.
Kjelll Stayv owns a small hotel in Vava'u and told Pacific Beat there is an eerie feeling in the air.
"The skying is milky and grey so there is definitely something coming," he said.
He says preparations for the cyclone are underway.
"On our island and the small outer islands here, there are between 10,000 to 12,000 people," he said.
"And right now there are now many tourists, maybe 100.
"It is a little weird because we have to board up their windows, but they don't have much choice I'm afraid."
Fiji-based climate advisor Neville Koop says preparations must be made under such a threat.
"You need to be taking your preparations very seriously at this time (as) it does look like the damaging winds will start in Vava'u probably late tomorrow (Friday)," he said.
"So that is some good news for people in Vava'u, in that they will have some daylight tomorrow to do some more preparations."
© ABC 2014
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