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Incredible Destruction and at Least 21 Deaths in Fiji From Tropical Cyclone Winston

By: Bob Henson and Jeff Masters 5:32 PM GMT on February 22, 2016

At least 21 deaths had been reported by late Monday Fiji time as the island nation slogged through the daunting early stages of recovery from ferocious Cyclone Winston, the strongest tropical cyclone on record in the Southern Hemisphere. Officials expect the death toll to rise when they're finally able to reach outlying islands that were hit hardest by the powerful storm, said the BBC, and it would not be surprising if Winston ends up being the deadliest and costliest natural disaster in Fiji's history. Fiji's deadliest tropical cyclone in recorded history was Category 3 Cyclone Eric of 1985, which made a direct hit on the capital of Suva, killing 25.

Since satellite records began in 1970 (with high-quality satellite images only available since 1990), just eleven Cat 5s (including Winston) have been observed anywhere in the South Pacific east of Australia. Winston is the strongest of these, according to records from the Joint Typhoon Warning Center. As Winston passed over Fiji’s Koro Island on Saturday, its winds were estimated by satellite at 180 mph (note: Winston was originally assessed to have 185 mph peak winds, but these were reduced to 180 mph in post-analysis.) This puts Winston in fifth place for Earth's strongest landfalling tropical cyclone on record. The only stronger storms were 2013's catastrophic Super Typhoon Haiyan (190 mph winds in Samar, Philippines), 2016's Super Typhoon Meranti (190 mph winds on Itbayat Island in the Philippines), 1959’s Typhoon Joan (185 mph winds in Taiwan) and the 1935 Labor Day Hurricane in the Florida Keys (185 mph winds). Wind speeds of 180 mph are characteristic of an EF4 tornado, and damage photos from the New Zealand Air Force showed many areas of incredible damage characteristic of at least EF3 tornado speeds (136 - 165 mph) on Koro Island (Figure 1.)


Figure 1. Wind damage in the village of Vatulele, on the northeast tip of Koro Island, Fiji. Tropical Cyclone Winston was at peak strength with 185-mph winds (Category 5 strength) when the eye passed directly over this village on February 20, 2016. Without knowing the quality of the construction, a good guess is that damage in this photo is from EF3 tornado wind speeds (136 - 165 mph), implying that this portion of Koro did not receive the full force of Winston's winds. This may be because high terrain behind this village blocked the full force of the wind--similar to what happened in Tacloban, Philippines, during the landfall of Super Typhoon Haiyan when it was at Category 5 strength. Image credit: Fijian government Facebook page.


Figure 2. Infrared imagery of Hurricane Winston as it bore down on the northeast coast of Fiji’s largest and most populous island, Viti Levu, on February 20, 2016. Koro Island (not shown) is located beneath the eastern eyewall of Winston, with the eye of Winston having passed directly over the island. Image credit: NOAA Weather Prediction Center.

A terrible track
Despite its relatively small size, Winston successfully took aim at Fiji along an unusual and especially destructive track. The cyclone had arced well south and east of Fiji last week before doing a 180-degree reversal in track and heading westward toward Fiji, strengthening from Category 2 to Category 5 en route. The storm’s powerful eyewall passed directly over several smaller islands and ground across the northern coast of Viti Levu, Fiji’s largest and most populous island. Photos taken from aboard New Zealand Air Force planes on Sunday, Feb. 21, 2016, and posted by the Fiji government on Facebook revealed the extent of the devastation from Winston on the island of Koro (see Figure 1) as well as Lau and Taveuni. The more highly touristed areas of Fiji, largely on Viti Levu, experienced relatively little damage, and no tourist casualties have been recorded, according to a Guardian report. On the west side of Viti Levu, Nadi International Airport resumed limited operations on Sunday, which will greatly facilitate relief efforts at the more remote islands. Most of the damage from WInston was due to the storm's extreme winds, though storm surge expert Hal Needham documented evidence of a storm surge of up to ten feet (3 meters) in a Monday blog post.


Figure 3. Cyclone Winston has carried out a large counterclockwise loop since its designation as a tropical cyclone on Feb. 10, 2016 (beginning of track at upper left). This tweet from Dan Lindsey includes a 12-day loop of Winston imagery from Japan’s Himiwari-8 satellite.

Patricia and Winston: strongest cyclones in Northern and Southern Hemisphere records
Remarkably, both the Northern and Southern Hemisphere have experienced their strongest cyclones in decades of record-keeping in the space of the last five months. NOAA recently announced the result of its post-storm analysis of Hurricane Patricia from October 2015, which spun up phenomenal sustained winds of 215 mph--the strongest ever measured by instruments via Hurricane Hunter aircraft--as the storm was approaching the Pacific coast of Mexico. Like Winston, Patricia was a relatively small storm, so its central pressure was not as low as its fierce winds might imply.

Since early 2015, we have had four Category 5 landfalls: Tropical Cyclone Pam (Vanuatu), Super Typhoon Maysak (Micronesia), Super Typhoon Noul (Philippines), and Cyclone Winston (Fiji). (Patricia was a strong Category 4 at landfall.) Although several of these tropical cyclones left major devastation in island nations that have relatively modest resources, we can take some comfort in the fact that none produced the kind of tragic death toll that occurred when Haiyan came ashore in the central Philippines. Haiyan was a large and fearsomely strong typhoon to begin with, and its destructive power was greatly exacerbated by its track into a large city on a shallow coastline prone to storm surge. The same could have easily occurred with several recent Cat 4s/5s: for example, only a slight eastward jog could have sent Patricia into Manzanillo Bay and the city of Manzanillo, Mexico. The very rapid strengthening of both Patricia and Winston--well beyond official forecasts in both cases--is a sobering reminder of the potential of real catastrophe in many areas, including the United States.


Figure 4. 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.

Climate change and Category 5s
In 2015, Earth saw a total of nine Category 5 storms, the second-highest total on record. This explosion of cyclonic fury was fed by ocean temperatures that were at record-warm levels globally, with especially warm readings across tropical and subtropical areas. El Niño has played a large role over the last few months by spreading warm surface water across vast swaths of the Pacific. However, Earth has also experienced a decade of intensified oceanic heat storage (which largely explains the temporary slowdown in the rate of atmospheric warming from about 2000 to 2012).

Tropical cyclones are heat engines at heart: they transfer energy from low-latitude oceans to the higher-latitude atmosphere. As human-produced greenhouse gases continue to pump energy into Earth’s oceans (where more than 90% of the excess heat from those greenhouse gases is stored), it is no surprise that some of that heat is being expressed in the form of record-setting typhoons, hurricanes, and cyclones. Now that ocean temperatures are considerably warmer than they were a few decades ago, the maximum potential intensity a hurricane can reach is higher. Climate models generally agree that we can expect a greater proportion of Earth’s tropical cyclones to attain Category 5 strength over the coming decades.

At Discover's ImaGeo blog, Tom Yulsman has an excellent distillation of Winston's connections to climate change as well as El Niño and the Madden-Julian Oscillation.

UNICEF and Save the Children are asking for donations to assist in Fiji relief efforts.

Dangerous weather brewing for Tuesday along Gulf Coast
We're keeping our eye on an expected outbreak of severe weather on Tuesday that could bring several strong tornadoes along the central Gulf Coast. Watch for more details here on Tuesday.

Bob Henson and Jeff Masters


Figure 5. Expected change in Atlantic Category 4 and 5 hurricanes per decade expected by the year 2100, according to Knutson et al. (2013), "Dynamical Downscaling Projections of 21st Century Atlantic Hurricane Activity: CMIP3 and CMIP5 Model-based Scenarios." This research used the latest generation of climate models from the 2013 IPCC report, and found "marginally significant" increases in Atlantic Category 4 and 5 hurricanes of 39% - 45% by 2100.


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.