Meranti Was a Super Typhoon for the Record Books

Super Typhoon Meranti near peak strength on September 14, 2016. Image credit: University of Wisconsin-Madison/Google Earth

The western Pacific Ocean is known to harbor some nasty typhoons, but Super Typhoon Meranti is a rare breed of danger. This powerful cyclone, which made landfall in China on Thursday, September 15, now sits in the record books as one of the most powerful tropical cyclones ever recorded in the Northern Hemisphere, and the strongest storm on Earth in 2016. The storm did hit some populated areas, but the worst conditions missed the largest city centers, sparing southeast Asia from the full horror of yet another scale-topping typhoon.

Super Typhoon Meranti peaked on Wednesday with maximum sustained winds of 190 mph before it scraped the southern tip of Taiwan and moved northwest toward mainland China, which would make it the equivalent of a category 5 on the Saffir-Simpson Hurricane Wind Scale.

To put Meranti’s ferocity into perspective, we only have reliable records of one hurricane in the Atlantic Ocean (Allen in 1980) reaching maximum winds of 190 mph, and Meranti is now among the top 10 strongest storms ever recorded in the Pacific Ocean. The typhoon’s lowest surface air pressure also dipped below 900 millibars, which places it among only a handful of storms to achieve this feat. Standard air pressure at sea level is 1013 millibars, and under normal conditions at sea level, the atmospheric air pressure doesn’t drop below 900 millibars until you’re a few thousand feet above the surface.

A radar loop of Super Typhoon Meranti as it approached the southern tip of Taiwan on September 14, 2016. You can see the typhoon’s eye wobbling in this loop. Image credit: Central Weather Bureau/Brian McNoldy

 
The piercing eye of Super Typhoon Meranti tracked just a few miles off the southern tip of Taiwan, focusing some of its strongest winds on Hengchun Township (population 30,000), but thankfully the core of the worst winds missed land. Residents of southern Taiwan were even more fortunate that Meranti didn’t make landfall as the storm’s eye was going through cycloidal oscillations as it drew closer to the island nation.

Cycloidal oscillations occur when the eye itself wobbles in a looping motion as strong thunderstorms bubble up in the eyewall and “tug” the eye toward them. As these strong storms rotated around the eyewall, they kept tugging the eye in their direction, causing the eye to wobble around as the whole storm kept moving northwest. If you traced these wobbles on a map, it would create little squiggles in the storm’s track. It doesn’t seem like much, but even a tiny shift in the eyewall’s location could mean the difference between a devastating storm and complete destruction.

While Taiwan missed the absolute worst of the storm, areas nearby weren’t so lucky. The island province of Batanes makes up the northernmost part of the Philippines, and this archipelago found itself directly in Meranti’s eyewall on Tuesday night and Wednesday morning.

An infrared satellite loop of Super Typhoon Meranti making landfall on Itbayat Island in the northern Philippines. Image credit: University of Wisconsin-Madison

 
The typhoon, which is known as “Ferdie” instead of Meranti in the Philippines, made landfall on the tiny island of Itbayat early Wednesday morning around sunrise, unleashing its full fury on the tiny strip of land that’s about 40 percent the size of Guam and home to around 3000 people. Due to one of those eye wobbles, the entire island fell within Meranti’s eye with room to spare, giving residents a brief reprieve before the extreme winds ripped back from the other direction. The typhoon severed all lines of communication between Batanes province, which includes Itbayat, and the rest of the Philippines Thursday morning. By the time it moved out, it had done an estimated $4.7 million U.S. in damage to the province.

A report in the Taipei Times indicates that the storm injured nine people and caused damage across Taiwan, knocking out power to more than 700,000 homes and businesses during the height of the storm. A weather station in Hengchun Township recorded winds of more than 105 mph, which the paper reports is an all-time record there since the station was established in the late 1800s. Taiwan now faces $21 million U.S. in agricultural losses.

After hitting the Philippines and Taiwan, Meranti continued on to its final landfall in mainland China as a powerful but weakening typhoon. The storm fell below the equivalent status of a major hurricane by the time it hit the mainland early on Thursday morning, but the storm made landfall very near Zhangzhou, a city that’s home to nearly five million people—a larger population than Los Angeles. In all, 14 died, dozens were injured, and 14 more are still missing. Some 33 million people were relocated, and 1600 homes were destroyed.