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Super Typhoon Haiyan From Ground Zero: a New Video Record

By: Josh Morgerman 3:47 PM GMT on December 02, 2013

This guest post and video is from veteran storm chaser Josh Morgerman of West Hollywood, California, who rode out Super Typhoon Haiyan in Tacoloban in the Philippines. Josh is the founder of of iCyclone.com, and has been chasing tropical cyclones since 1991.

Super Typhoon Haiyan (Yolanda to the Filipinos) is one of the biggest weather catastrophes of the past decade. A Category-5 storm making a direct hit on a city of 220,000 is going to make news.

I chased Haiyan to ground zero--Tacloban City--where I rode out the cyclone with fellow storm chasers James Reynolds and Mark Thomas. Our location: Hotel Alejandro, a four-story, solid-concrete building in the heart of downtown, 26 feet above sea level. (Coordinates:11.2414N 125.0036E.)

A safe place. Or so we thought.

I just released this short video that tells the story of that terrible morning--in graphic, frightening detail.



As the wind rose to a scream, as windows exploded and doors blew off, as the building trembled from the impact of flying debris and as children became hysterical, a massive storm surge swept the entire downtown, inundating the hotel and sending guests scrambling for their lives. My fellow chasers and I had to throw down our cameras and pull elderly and disabled guests out through the smashed windows of flooded rooms.

And we were the lucky ones in Tacloban City.

While whole blocks were reduced to rubble, our building stayed standing. And while thousands died--including people on our very block--I’m very happy to say that everyone in our hotel (and everyone you see in my video) survived. This includes the family you see struggling across the storm surge to reach our hotel. (One of the most serious injuries was actually on our own team: while trying to rescue a trapped guest, Mark tore open his leg on underwater wreckage, and weeks later he’s making a very slow recovery at home in Taipei.)

Video as Meteorological Record
My video’s many viewers have reacted strongly to the raw power of the storm and the spectacle of ordinary people trying to survive a life-and-death situation. This is understandable.

But I want to also point out that my video is a useful meteorological record.

When I chase, I always stamp my video footage with the exact local time, so afterward I can compare conditions on the ground with other data--to try and understand what happened.

So my Super Typhoon Haiyan video serves as detailed chronology of the event. Combining it with air-pressure and storm-surge data I collected during the event, we can learn a lot about this unique and ferocious cyclone.

Haiyan Video Chronology
First off, here are some important events and details to notice in the video:

6:47 am. The eyewall sweeps into the city. Winds rapidly increase and rain becomes very heavy. Notice the trees are full and green.

7:08 am. In narration, I note the pressure is 962 mb. This was close to the lowest values my devices recorded (960.8 mb and 960.3 mb at 7:12 am and 7:20 am, respectively)--meaning the center was passing just south of the city and making its closest approach about this time.

7:13-7:25 am. The winds reach a peak. Tornado-like conditions engulf downtown. We never experience a calm--meaning the eye misses us to the south.

7:44 am. The storm surge sweeps in suddenly. The street is completely flooded, whereas just minutes earlier, we hadn’t noticed any water.

8:00-8:30 am. Water is up to the first-floor door handles and windows. (You can see this in the rescue shot--donated by Earth Uncut TV--that follows 7:57 am. It’s not time-stamped but certainly occurred between 8 and 8:30 am.)

8:45-8:46 am. The storm is dying down. Winds are slacking and the water is already noticeably receding--it’s much lower against the doors and windows.

8:57-9:00 am. All deciduous trees across the city are completely stripped--with no leaves. (Palms performed a little better.)


Figure 1. Haiyan, the aftermath: extreme storm surge damage in Tacloban. Image credit: Josh Morgerman, iCyclone.com.

Conclusions
Using the above video events and details—along with other data—we can draw a few conclusions about Super Typhoon Haiyan when it made landfall in Leyte, just south of Tacloban City:

The typhoon’s core was small. As per the video, the storm didn’t last long. Winds in the city didn’t become violent until only 30 minutes before the center’s closest approach, and really destructive winds lasted only 2 hours (~6:45 - 8:45 am). Even taking into account Haiyan’s fast forward motion, it’s clear the storm was on the small side--despite news reports to the contrary. It’s a testament to Haiyan’s incredible ferocity that it was able to completely devastate Tacloban City in such a short time.

The northeast eyewall was strongest. The storm was moving west-northwest and the highest winds seemed to occur during and after the lowest pressure. This is consistent with the radar imagery, which showed the strongest convection in the northeast quad.

Tacloban City experienced extremely high winds--at least Cat 3 and possibly Cat 4, since we saw complete defoliation and evidence of debarking of deciduous trees. This is especially impressive given that the highest winds didn’t last long--and I should point out that it’s exceedingly unusual for an urban area to experience such intense winds. While Haiyan was a Cat-5 storm and Tacloban City was squarely in its north eyewall, we believe the RMW (radius of maximum winds) passed just south of downtown.

The storm surge was tremendous, fast-moving, and short-duration. USGS data and other sources indicate the elevation at our location was 26 feet. Since the hotel flooded to a depth of 4 feet, that suggests the surge may have been an incredible 30 feet! (Even if we’ve overestimated our elevation by 10 feet, that’s still a huge 20-foot surge.) But it didn’t last long. It swept in very suddenly around 7:45 am and was already receding by 8:45--meaning it did its deadly work with incredible speed. This is very different than Hurricane Ike, a large storm that caused large-scale inundation more than a day before landfall.

Josh Morgerman, iCyclone.com

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.