Cyclone Ian picks up strength in Pacific
A cyclone north of New Zealand was this evening declared to be a major storm threatening a large area of Tonga, home to 110,000 people.
Tonga's Meteorological Service warned tonight that Cyclone Ian had become a category four cyclone, one short of the most intense storm on the scale.
Ian formed earlier this week as the summer season's first cyclone and had meandered around the Koro Sea - between Fiji and Tonga - without threatening settlements but has now gained strength.
Its latest warning says the northern Vava'u group is facing the first hit from Ian while a gale warning is in force for the Ha'apai group.
"Tropical Cyclone Ian has estimated winds of 139 kph near its centre with momentary gusts of up to 176 kph."
Ian is continuing to intensify and is now moving south east.The service warns flash flooding can be expected with seas becoming rough to very rough.
Earlier today the US space agency Nasa released data from its Aqua satellite which showed powerful thunderstorms surrounding Ian's centre of circulation.
"The strongest thunderstorms were concentrated around Ian's centre and in bands north and south of the centre where cloud-top temperatures exceeded minus 52 degrees Celsius," Nasa said.
"Those thunderstorm cloud tops have cooled over the previous 24 hours, indicating that they're higher in the atmosphere and that Ian is strengthening."
Ian was centred about 500 kilometres east-northeast of Suva, Fiji.
If Ian later this week heads off south into the Pacific, an 86-year-old sailing training ship Picton Castle could be in harms way.
It took part in the Auckland Tall Ships Festival in December and left Opua on December 29.
The ship, based in Nova Scotia, flies a Cook Islands flag and is heading for Rarotonga as part of a global voyage.
This morning it gave its position as 41 degrees south, 163 degrees west and doing 13kmh.
Crew on board this morning tweeted that they were watching the storm: "We've got our eye on it!"