The main island in Tonga, Tongatapu, and surrounding smaller islands will shortly feel the effects of winds from cyclone Vaianu as it continues on its south-west path.
The lead forecaster at the Fiji Met Service, Ali Pate, says the cyclone, which is located at 19.1 south and 176.9 west, has winds of 110 kilometres at its centre.
And, he says these are expected to intensify to about 120 kilometres an hour during the day.
Mr Pate says cyclone Vaianu is expected to move gradually to a southerly direction.
"Currently, the indications are - it may slip south between Fiji and Tonga. If anything, it might bring gale force winds over Nuku'alofa and nearby smaller islands. As far as Fiji is concerned, it might just bring strong winds."
The lead forecaster at the Fiji Met Service, Ali Pate.