Tropical Cyclone Tino strengthened to a Category Three storm Saturday as it closed in on Tonga after battering Fiji where two people were missing and more than 3,000 fled to emergency shelters.
The Fiji Meteorological Service said the wind gusts from Tino had increased to 180 kilometres per hour (110 mph) and would likely have its biggest impact in the northern areas of Tonga when it hits overnight.
The Pacific kingdom is still recovering from the devastation of Cyclone Gina two years ago which caused widespread devastation, destroying houses and crops.
"The sea is very high and I'm sure beaches are being washed away in the more exposed places and the outer islands," Tupoutu'a Tonutonu told AFP from northern Vava'u.
"It's been bucketing down for about three days, the soil is waterlogged and I'm hearing trees are down in the village."
In Fiji, the National Disaster Management Office said 3,115 sought emergency shelter at the height of the storm, but most had since returned home with damage not as severe as first feared.
"We know for sure most of them went to the EECs (evacuation centres) to take shelter because of the big rains we were receiving and also because of the warnings," Uraia Rainima, a senior government official in the northern region, said.
"We have received information that most of them are moving back to their houses."
The island of Taveuni, with a population of around 19,000 people, was without power, Rainima said.
Police, meanwhile, continued the search for a father and his daughter who were swept away when they tried to cross a swollen river on Thursday evening, and said there were no other casualties.