The Meteorological Service in Fiji says Cyclone Mick is weakening as it heads towards Tonga.
It says a tropical cyclone alert is now in force for the Tongatapu island group in Tonga.
It says Cyclone Mick was relocated to about 500 kilometres west-northwest of Nuku'alofa at midday.
Close to its centre the cyclone is estimated to have average winds of 35 to 40 knots with momentary gusts to 60 knots.
The cyclone is currently moving southeast at 10 knots.
If it maintains its current intensity and its forecast track, it may bring damaging gale force winds over the Tongatapu and Eua island groups in the next 24 to 36 hours.