A tropical storm is brewing in the South Pacific and could become a cyclone within 24 hours.

MetService meteorologist Bill Singh said a tropical depression was sitting north of Fiji.

It was expected to deepen overnight and there was a good chance it would be named the region's latest Tropical Cyclone later today.

He said the storm system was slow moving and regarded to be ripe for intensifying in coming hours.


"It's getting everything that should be able to help it to develop," said Mr Singh.

"It should deepen further tonight and Fiji MetService is saying in the next 48 hours a system of tropical intensity should be formed."

He said computer models showed the cyclone would alter its northwest course and track in a south-easterly direction towards the weekend, passing between Tonga and Samoa next week.

At this stage cyclone-battered Fiji would be spared the worst, save strong winds affecting the northern group of islands.

Mr Singh said it was too early to predict the level of intensity the forming cyclone would reach.

Cyclone Winston, the most powerful storm ever recorded in the Southern Hemisphere, moved through the Pacific in February causing death and destruction across Fiji.