Tongan Met Service said gale force winds were forecasted to hit the Tonga groups on Tuesday night and Wednesday.
It said a heavy rain and flash flood warning remains in force for all of Tonga.
Tropical depression 14f lies near latitude 18.5 s longitude 178.8 w or 470km northwest of Tongatapu or 485km northwest of Lifuka or 500km west of Neiafu at 11pm tonight.
The system is moving southeast towards the group at a speed of 15 knots (28km/hr), associated clouds with occasional rain and damaging gale force winds may affect the group.
For Ha’apai, Vava’u and the Niuas:
Moderate to fresh northwest winds increasing to strong and damaging gale force winds by tonight and tomorrow.
Mostly cloudy and overcast with occasional rain heavy at times with possible isolated thunderstorms.
A flash flood especially for coastal and low lying areas.
For Tongatapu and ‘Eua:
Moderate to fresh east to southeast winds becoming strong to gale force winds at times from tonight and tomorrow.
Mostly cloudy and overcast with occasional rain heavy at times.
