Fiji's acting chief fire officer says people in low-lying parts of the flood-affected Western Division shouldn't wait to move to higher ground.
The National Disaster Management Office says water levels from heavy rain that began overnight on Thursday look likely to be higher than those in January, when flooding caused extensive damage.
It says all the schools in the district have been closed for the day and all domestic and international flights in and out of Nadi have been suspended.
Qio Moceitai says the fire service has had to evacuate people in Tavua and Lautoka trapped by flooding.
"The people should be more proactive at this time when the flood has not come to their steps. They should be moving away from low-lying areas to prevent people getting trapped in the flood."
Qio Moceitai says all of Fiji's fire stations are on alert because of the flooding.