Tropical Cyclone Mal has been upgraded into a category 2 system on Tuesday morning but is currently on track to miss New Zealand.
The Fiji Meteorological Service said Mal is expected to pass close to the west of Fiji on Tuesday evening (local time) with the centre likely to lay approximately 170km west of Nadi at 3am on Wednesday morning.
"It may begin to have an impact on Yasawa and Mamanuca from later today," Fiji Meteorological Service said.
MetService said Mal is expected to stay "well away" from New Zealand, continuing to move to the southeast.
Forecaster Samisoni Waqavakatoga told RNZ the system is expected to reach the high end of category two at its peak strength.
But he warns it could potentially reach category three with average winds surpassing 119km/h.
"There is a possibility it could reach category three but for now, like I said, we've just been maintaining it at the high end of category two, we're not jumping any guns here but if the environment is still favourable it could reach category three status," Waqavakatoga said.
Fiji Meteorological Service has issued a flash flood warning for the low-lying areas of Qauia, Lami Marata Village and Wailoku. A flash flood alert is also in place for low-lying areas of Coral Coast to Navua, Lami, Suva, Nausori, Tailevu, Naitasiri and Ovalau.
The Fiji National Disaster Management Office has reported several bridges and crossings are inaccessible and is urging people to stay away and avoid crossing flooded roads, rivers, bridges, crossings, or walkways.
Schools in Fiji are closed on Tuesday and Wednesday and all public servants have been instructed to work from home, RNZ reports.
Assistant police commissioner operations ACP Livai Driu is calling for the "strict supervision of children stressing, this is not the time for children to be playing outdoors or swimming".
