The depression is expected to intensify into a category one tropical cyclone in the next 6 to 12 hours. Photo: Fiji Meteorological Service
A tropical cyclone alert is in place for the Southern Cook Islands.
The tropical depression (TD06F) is expected to intensify into a category one tropical cyclone in the next 6 to 12 hours.
It is expected to bring gale force winds over the Southern Cook Islands with associated rain and thunderstorms.
Fiji Meteorological Service senior scientific officer Iosefo Cauravouvinaka told RNZ Pacific the tropical disturbance is about 650 kilometres northwest of Aitutaki - the second-most populated islands in Cook Islands.
The tropical dipresssion is moving at about 50 kilometres per hour in an east south-east direction, he said.
Cauravouvinaka said the system is expected to become a cyclone but not surpass category 1 strength - the weakest cyclone category.
"As it moves into the [Southern] Group it moves into an unfavourable area of cooler water as it moves into the south.
"So potentially if it intensifies it will be just the high end of category 1."
He said that would bring sustained winds close to the centre of about 83kmph and gusts between 90 to 120kmph.
He said cyclone is tracking to remain in the north of the Southern Cook Islands.
Palmerston, Aitutaki and Mauke would be worst effected but the centre of the cyclone is expected to remain at sea, he said.
Cauravouvinaka said the cyclone is expected to bring isolated damage to trees or homes with light materials.
"Those communities along the coast might be most affected."
However, he said the cyclone may only have a minimal impact.
