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Winston's 180 mph Winds in Fiji: Southern Hemisphere's Strongest Storm on Record

By: Jeff Masters 6:47 PM GMT on February 20, 2016

The strongest storm in recorded history for the Southern Hemisphere--mighty Category 5 Tropical Cyclone Winston--smashed through the islands of Fiji Friday night and Saturday morning with top sustained winds estimated at 180 mph (note: Winston's top winds were originally estimated at 185 mph, but these were reduced to 180 mph in post-analysis.) These winds vaulted Winston into a tie as the third strongest landfalling tropical cyclone in world recorded history (see Figure 3). Winston began its march at Category 5 strength through the Fiji Islands beginning at 18 UTC (1 pm EST) Friday. At that time, Winston had 165 mph winds as it moved westwards over the small Fiji island of Vanua Balavu (population 1,200). The island's airport was in the western eyewall of Winston, and at 18 UTC measured 10-minute average winds of 106 mph (roughly equivalent to 120 mph winds using the U.S. 1-minute averaging time.) Winston continued to intensify, then crashed ashore on the Fiji island of Koro (population 4,500) at peak strength--sustained winds of 185 mph--near 02 UTC Saturday (9 pm EST Friday.) This is the third strongest landfall by any tropical cyclone, globally, in recorded history. Only Super Typhoon Haiyan's 190 mph winds at landfall in 2013 in Samar, Philippines, and Super Typhoon Meranti's 190 mph winds at landfall in Itbayat Island, Philippines have been rated higher. After likely demolishing most of Koro with a long period of sustained winds of EF4 tornado strength, Winston's northern (weaker) eyewall brushed the south coast of Fiji's second largest island, Vanua Levu. The city of Nambouwalu on the south coast of Vanua Levu reported 10-minute sustained winds of 121 mph at 06 UTC Saturday (roughly equivalent to Category 4 winds of 135 mph using the U.S. 1-minute averaging time.) Winston then wobbled more to the west-southwest, possibly due to interaction with the high terrain of the two largest islands of Fiji. Maintaining winds of 180 mph, Winston slammed ashore along the northeast coast of Fiji's main island of Viti Levu in Rakiraki, a district of close to 30,000 people, near 07 UTC Saturday. The eye of Winston travelled westwards along the north coast of Viti Levu for two hours, pounding the entire north coast of the island with the strongest part of the storm, the southern eyewall. When Winston finally emerged from the island near 09 UTC Saturday, the storm was slightly weaker, but still had Category 5 winds of 160 mph. At that time, the edge of Winston's south eyewall moved over the second largest city in Fiji, Lautoka (population 80,000). The top sustained winds at the Lautoka tide station were 83 mph, gusting to 110 mph. These 10-minute average winds imply that at least Category 2 hurricane conditions (95 - 100 mph 1-minute averaged winds) were likely experienced there (thanks go to wunderground member Carnivorous for this link.) Damage to Fiji is going to be severe to catastrophic, but it will be several days before the true scope of the destruction is realized.


Figure 1. Radar image from the Fiji weather service showing Tropical Cyclone Winston at 07 UTC Saturday, February 20, 2016. At the time, Winston was making landfall on Fiji's main island of Viti Levu as a Category 5 storm with 180 mph winds and a 915 mb central pressure.


Figure 2. Visible MODIS image from NASA's Terra satellite of Tropical Cyclone Winston taken at 0300 UTC February 20 (10 pm EST February 19), 2016. At the time, WInston was a Category 5 storm with 185 mph winds, and its eye was over Koro Island on Fiji. Image credit: NASA.

Winston the strongest tropical cyclone on record in the Southern Hemisphere
Winston's 180 mph sustained winds at its peak intensity at 00 UTC February 20 are tied for the highest for any Southern Hemisphere tropical cyclone ever rated by the Joint Typhoon Warning Center (JTWC). The other 180 mph cyclones were Cyclone Zoe of 2002 and Cyclone Monica of 2006. Winston's lowest central pressure as estimated by the Fiji Meteorological Service was 915 mb at 06 UTC February 20. This ranks Winston as the 29th most intense tropical cyclone in the Southern Hemisphere by pressure. The record lowest pressure is 890 mb by Cyclone Zoe of 2002. Winston's top winds were higher than its central pressure might imply because it was a relatively small cyclone, so the wind-generating difference in pressure was packed into a small area. Winston joins a very select club of Category 5 storms ever recorded to churn the South Pacific waters east of Australia. Since satellite records began in 1970 (with high-quality satellite images only available since 1990), just eleven Cat 5s (including Winston) have been observed in the South Pacific east of Australia. Only two of the ten previous Cat 5s have made landfall as a Category 5. The most recent was last year's Cyclone Pam, which was at its peak strength, with 165-mph Category 5 winds, when it passed over several small Vanuatu Islands to the north of Efate Island, Vanuatu's most populous island. The other Category 5 landfall was by Cyclone Zoe of 2002, which made a direct hit as a Category 5 storm on several small islands in the Temotu Province of the Solomon Islands with a total population of 1700. There was one other close call, though: the eye of Category 5 Tropical Cyclone Olaf passed 15 miles east of Ta'u, American Samoa, on February 16, 2005, but caused minimal damage.


Figure 3. The most intense world tropical cyclones at landfall, using the advisories taken from the National Hurricane Center in the Atlantic and Eastern Pacific, and the Joint Typhoon Warning Center (JTWC) for the rest of the world's oceans. Both agencies use 1-minute averaging times for their advisories, as opposed to the 10-minute averaging time used to report wind speeds by most international weather agencies and at most international airports. Note that Super Typhoon Haiyan was originally assessed to have 195 mph winds at landfall by JTWC, but these were reduced to 190 mph after a post-season reanalysis. Also, Hurricane Camille's winds at landfall have also been reduced in a recent reanalysis, from 190 mph to 175 mph.


Figure 4. Track of all Category 5 storms in the South Pacific (east of 135°E) since satellite records began in 1970. The strongest tropical cyclones in the Joint Typhoon Warning Center’s records are Zoe (2002/2003) and Monica (2006), which topped out with 180 mph winds. Image credit: Michael Lowry, TWC.

Forecast for Winston
Winston has moved past Fiji, and is no longer a high wind threat to the islands. Some residual heavy rains will continue over the western portion of Viti Levu on Saturday, though. Winston will likely weaken to Category 4 strength and head southwards during the remainder of the weekend, with no other islands in its path, thankfully. The cyclone may restrengthen slightly on Monday before a more significant weakening takes hold.

Fiji's tropical cyclone history
Category 4 Tropical Cyclone Evan of December 17, 2012 walloped Fiji with sustained winds of 135 mph, as the storm's southern eyewall--the most intense part of the storm--brought hurricane conditions to a long stretch of the north and west coasts of Fiji's main island, Viti Levu. According to a database maintained by NOAA's Coastal Service Center, Evan was the strongest tropical cyclone on record to affect Fiji's main island, with records going back to 1941 (however, more accurate satellite records extend back to only about 1990.) Evan did $109 million in damage (2012 dollars) to Fiji, making it the second most destructive storm in their history. The most devastating cyclone to affect Fiji in recorded history was Category 2 Cyclone Kina of January 1993, which killed 23 people and did $100 million in damage (1993 dollars.) The only deadlier storm than Kina was Category 3 Cyclone Eric of 1985, which made a direct hit on the capital of Suva, killing 25.


Figure 5. Tracks of all Category 1 and stronger tropical cyclones to pass within 100 miles of Fiji's main island of Viti Levu since 1941. Evan of 2012 (Category 4 with 135 mph winds) was the strongest cyclone on record to affect Fiji, but Winston of 2016 was much stronger. Image credit: NOAA's Coastal Service Center.

Links
Radar images from the Fiji weather service
Long radar loops of Winston
Satellite imagery from NOAA/NESDIS.
Fiji weather observations from wunderground.
Long Himawari-8 satellite animation in MP4 or animated GIF format.
Fiji Met Service Facebook page.


Cyclone Winston: Incredible conditions in Savusavu, Fiji, February 20, 2016. (Thanks go to wunderground member barabmz for posting this video in the comments.)

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.