Tropical Cyclone Winston is expected to make landfall on Fiji’s main island Saturday night, local time (Saturday morning, Eastern Time), as a strong Category 4 on the Saffir Simpson Scale. There is no record of a hurricane so strong making landfall on Fiji’s main island. (NASA)

A destructive tropical cyclone is bearing down on Fiji with winds approaching 150 mph and an intensity rating that is nearly off the charts. Tropical Cyclone Winston is the worst case scenario for Fiji — a Category 5 that is expected to make direct landfall on the most populous island, home to the capital city of Suva.

Winston took an incredibly unusual path to get to where it is right now — winding through the South Pacific and crossing over a single island twice. The cyclone passed Tonga’s island of Vava’u once earlier this week as a category 2, and then strengthened, turned and passed over the same islands again as a category 4. Australia’s ABC News reports that Vava’u fared better than expected as Cyclone Winston passed by.

Cyclone Winston could prove to be Fiji's most powerful on record, packing winds of 145 mph and gusts of up to 180 mph. It's rated category 5, the highest ranking on the hurricane wind scale. (Reuters)

Since then, Winston grew even stronger, exploding into a category 5 cyclone on the Australia scale, with 145 mph winds — the equivalent of a strong category 4 hurricane in the Atlantic. The Fiji Meteorological Service estimates that Winston’s wind gusts are 295 kilometers per hour, or around 180 mph.

In regions of the world where direct observations, like hurricane hunters, are not available, satellite estimates are used to ascertain the intensity of the cyclone. This method is called the Dvorak technique. After all the elements of the storm are analyzed — things like cloud cover, the eye, banding and shear — a final Dvorak number is given on a scale from one to eight. On Friday, Winston was given an eight.

This would suggest the cyclone is much stronger than the current 145 mph wind speed estimate, and that it could be harboring wind speeds up to 190 mph.

Though Fiji is prone to tropical weather in the South Pacific, the main island of Viti Levu doesn’t necessarily have a history plagued with disastrous cyclones.

Looking back through the records, which are admittedly short, the last time a tropical cyclone of this strength came this close to Fiji’s most populous island was 2012, when Cyclone Evan passed just to the west of the island as a Category 4 on the Australian scale. Before that, we have to look to 1990, when Cyclone Sina passed to the south as a Category 3 on the Australian scale.

But no cyclone of this severity has made direct landfall on the island, which is what Winston is expected to do. In fact, the strongest cyclone to make direct landfall on the island did so over 30 years ago: Nigel in 1985, with 120 mph winds.

A false sense of security may be working against preparation efforts on the island of Viti Levu. “Most of the people in Suva are under the misapprehension that Suva doesn’t get cyclones — that it’s only the north and the west of the country that seems to get them and the ones that come past Suva are weak and insipid,” Fiji Meteorologist Neville Koop told Australia’s ABC News

“This is the exception to that — it’s probably one of the strongest cyclones to affect the capital in the last decade or two,” he added.

On Feb. 11, 2016 NASA's GPM instrument saw rainfall rates of over 2.4 inches per hour on the northwest side of Winston's eye wall. The highest clouds in the cyclone climbed 10.5 miles into the atmosphere in a strong band of thunderstorms that fed into the storm's center. (NASA.gov Video/YouTube)