Tropical Cyclone Oli is moving in a south eastern direction over the Cook Islands and has slowed down.
After moving away from the northern Cook Islands during Tuesday, Oli had dropped to about 14 knots by early evening.
The Fiji Meteorological service says the Southern Cooks could experience damaging gale force winds in the next day.
People have not been told to stay indoors but are being advised to take precautions and secure their homes in the event of strong winds.
Evaucation centres have been activated but at this stage there have been no reports of damage or injuries.