00:59 Atlantic Hurricane Goes Greek For only the second time the National Hurricane Center has run out of names so they have turned to the Greek Alphabet.

Several Southern Pacific islands are preparing for the impacts of Tropical Cyclone Winston, a system that poses a catestrophic threat of wind and rain as it approaches land.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/staticmaps/DCT_SPECIAL10_1280x720.jpg" srcset="https://s.w-x.co/staticmaps/DCT_SPECIAL10_1280x720.jpg 400w, https://s.w-x.co/staticmaps/DCT_SPECIAL10_1280x720.jpg 800w" > Tropical Cyclone Winston's current location

The intense storm is in a location that sees several tropical cyclones each year, on average, but this one has become quite powerful and had strengthened into a Category 5 equivalent Friday afternoon U.S. mainland time. With the Friday night advisory, Winston had sustained winds of 185 mph with gusts to 225 mph, making it the strongest tropical cyclone on record in the Southern Hemisphere.

"So far this century, an average of 5-6 tropical cyclones of at least tropical storm intensity have formed each year in the Southwest Pacific basin," said weather.com senior meteorologist Jonathan Erdman .

(MORE: Jan. 2016 Was Warmest January on Record )

Here are five important things you should know about this storm as it grows and prepares to lash several islands in the South Pacific.

1. It has already hit Tonga once, and side-swiped a second time

It's not often that a tropical system makes a U-turn and hits an area twice, but that's exactly what happened with this storm.

The first strike on Tonga from Winston left damage behind. According to Matangi Tonga Online, trees and power lines were brought down and homes were damaged in Vava'u, but officials said they haven't confirmed any injuries from the storm's first pass. Hundreds of residents went into shelters during the storm, and hurricane-force wind gusts were reported on the island early Tuesday morning, Matangi Tonga Online also said.

“We are thankful there has been no report of lives lost or injuries in all of the islands,” Deputy Prime Minister Hon. Siaosi Sovaleni told Parliament.

(MORE: Strong El Niño Could Transition into La Niña )

After passing Vava'u, the storm made a sharp U-turn, heading back toward northern Tonga and Fiji. According to the Joint Typhoon Warning Center, Winston could come dangerously close to Fiji's capital and largest city, Suva, this weekend.

Winston is forecast to make another sharp turn in the week ahead, but the cyclone may stay far enough west to spare Tonga for a third impact.

(INTERACTIVE: Tropical Cyclone Winston Forecast Path )

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/staticmaps/DCT_SPECIAL15_1280x720.jpg" srcset="https://s.w-x.co/staticmaps/DCT_SPECIAL15_1280x720.jpg 400w, https://s.w-x.co/staticmaps/DCT_SPECIAL15_1280x720.jpg 800w" > Projected Path and Intensity

2. Aid groups are already on these islands cleaning up from the first strike

New Zealand has already sent aid and money to Tonga as the nation cleans up from Winston's first strike and prepares for the next possible impact. The country pledged $39,000 as an initial response to the storm , according to Radio New Zealand International.

Carlos Calderon, Oxfam New Zealand's Pacific humanitarian manager, told the New Zealand Herald that supplies are already in Tonga and would provide up to 8,000 people with clean drinking water in the wake of the storm.

"Cyclone Winston is the second to hit Tonga this year," Calderon said. "Oxfam is supporting its community partners and we are ready to reach out with emergency supplies to those affected, should they need our help."

3. Fiji's capital doesn't see tropical cyclones all that often

Although records don't date too far back for Fiji's tropical weather, meteorologists know it's fairly rare for a tropical cyclone to hit the country's capital city.

"According to NOAA's Historical Hurricane Tracks database, only 12 tropical cyclones of at least Category 1 equivalent intensity have tracked within 100 miles of Fiji's capital and largest city, Suva, since 1972," said Erdman. "The last one to do so was Evan, just over a week before Christmas 2012."

(MORE: A Look Back at Cyclone Pam's Direct Hit on Vanuatu )

4. El Niño a factor in Winston's strength

It's the question on the minds of so many: as Winston grows stronger, what's the influence of El Niño? Experts say there's a possible correlation, but the pattern isn't the only thing making this storm grow into a monster.

"In El Niño years, South Pacific tropical cyclone activity tends to be greater toward the International Date Line, rather than in the Coral Sea near Australia," said Erdman. "While sea-surface temperatures are not the 'end-all-be-all' for tropical cyclones, warmer-than-average waters in the South Pacific are helping fuel Winston."

5. Officials fear the storm could spread disease in Tonga

Aid agencies are very worried Winston will further spread the Zika virus in the wake of the storm. According to a Reuters report, officials are concerned that the lack of mosquito control during the recovery period will allow the mosquito population to explode , putting citizens at a higher risk of contracting the virus.

As a result, aid groups have spent extra resources spraying areas that may be impacted by a mosquito population boom, removing larvae from water tanks and distributing nets – especially to pregnant women – the report also said.

An outbreak was declared in Tonga earlier in the month after five cases of Zika were confirmed and another 259 were suspected, Reuters added.

MORE ON WEATHER.COM: Earth's Weather from Space