Tropical Cyclone Yasa is just hours from making landfall, with Fiji bracing for a catastrophic storm bringing towering waves, widespread flooding and destructive winds.
The powerful category 5 cyclone - currently the strongest on the planet - is due to reach Fiji's second-largest island, Vanua Levu, at 8pm local time (9pm NZT).
Winds are now averaging 250km/h and gusting up to 350km/h close to the super-storm's centre.
Dangerous surges as high as 16m are expected to swamp coastal regions around high tide at 7pm, with the Fiji Meteorological Service issuing an urgent warning to anyone living near water.
At 11am the storm was located 215km north of Nadi and moving east-southeast at about 19km/h.
The National Emergency Operation Centre has been activated to coordinate the Fijian government's response and relief efforts.
Evacuations have already taken place in low-lying areas and all non-essential government workers have been told to stay home during the height of the cyclone.
The National Disaster Management Office this morning reiterated warnings of imminent danger, pleading with those living near the coast to move to evacuation centres as the storm approaches.
The office also threatened police action as taxis and buses defied orders to stay off roads.
Heavy rain is falling and squally thunderstorms are rumbling overhead as the first tropical cyclone of the region threatens to wreak havoc.
This afternoon Fijian Prime Minister Frank Bainimarama said over 850,000 people were in the direct path of the world's strongest storm.
He urged people to prepare, take cover, and pray.
The Meteorological Service said destructive winds were likely to begin several hours before the cyclone centre passed overhead or nearby.
Mid-morning parts of Fiji were already being battered by gusts of just under 100km/h.
At this stage the ferocious weather is expected to last through Friday before the cyclone sweeps through the island group.
All public transport has been halted as the storm, packing ferocious 260km/h winds, is expected to pummel the islands along with severe coastal flooding.
An Air New Zealand flight from Nadi to Auckland has been cancelled due to adverse conditions.
The disaster management office says coastal dwellers should expect storm surges with waves as high as 16m.
People were warned to secure homes and stow objects that could be blown away by strong winds or washed away by floods or storm surges.
The Fiji Meteorological Service has issued a damaging heavy-swell warning for Rotuma, Yasawa and the Mamanuca Group, Viti Levu, Vanua Levu and nearby smaller islands.
Aid agencies are preparing for a disaster and urging people to take precautions to keep themselves safe.
The Fiji Metservice said the slow-moving storm which was travelling around 11km/h was expected to be located about 320km south-southwest of Rotuma at 3am.
Wave height was expected to grow to 7m this morning with winds ramping up across the day.
It said gales were expected to hit from 3am and expected to further increase to reach "very destructive hurricane-force winds" by 3pm.
The Meteorological Service warned by Friday the whole of Fiji is expected to experience damaging winds or stronger, widespread heavy rain leading to landslides, severe flooding and burst river banks, storm surges, damaging heavy swells and high waves causing sea flooding in coastal areas.
It warned there was likely to be widespread destruction, with the strongest winds reserved for several hours either side as the cyclone centre passes overhead or nearby.
At 9am on Friday, the cyclone was expected to be located about 65km east-northeast of Yasawa-iRara, about 160km north-northeast of Nadi and about 460km south-southeast of Rotuma.