Haiyan - Philippines

MClarkson

MClarkson

EF5
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http://www.ssd.noaa.gov/PS/TROP/floaters/31W/31W_floater.html

That image says it all. Its the coldest most symmetrical cloud tops I have ever seen in a tropical cyclone. Even mighty storms like Wilma had a CDO that was less impressive than this. Katrina, Rita, Isabel, were far less impressive by comparison. In short, Haiyan is competing for the strongest cyclone ever observed, and the scary thing is that its nearing landfall at this strength!
 
Good day all,

Fellow chaser buddies of mine (Josh M and Jim Edds to name a few) have flown out to the little city of Tacloban.

On Nov 8 they were grazed by the northen fury of 195 MPH sustained winds. I cannot wrap my mind around this.

Gusts were to 230+ MPH when this came ashore. I wish them well (although I'm both apprehensive AND ENVY at the same time)!

South of their location, winds would be sustained at EF-4 (or even EF-5) tornado speeds...
 
I'm curious how the strength of this storm is being determined in public advisories and such. I tried looking up the storm status on wunderground and found no minimum central pressure information. Are the wind speeds being merely estimated based on Dvorak scale or are there any actual airplane or surface-based measurements of this storm? I imagine there are few surface-based weather observation platforms in the Philippines, but have there been any actual wind speed measurements on land from this storm?
 
Intensity and pressure were based on satellite. No recon flights, and no real sfc obs to speak of. I know there were a few places getting data out earlier in the day yesterday, including one that measured 95 mph sustained winds and something like 955mb pressure, but it failed well before landfall. There were a few chasers in Tacloban City and I assume they probably gathered some data, but they were a bit north of the eye. I hope some reliable obs were obtained in/near the eye, but I doubt it.

Given how extraordinary the satellite presentation was, I can't help but wonder if it was actually more intense than the advisories indicated at some point. One of the advisories mentioned trouble with the Dvorak numbers:

TXPQ25 KNES 072114
TCSWNP

A. 31W (HAIYAN)

B. 07/2030Z

C. 10.8N

D. 125.9E

E. ONE/MTSAT

F. T8.0/8.0/D0.5/24HRS

G. IR/EIR/SWIR

H. REMARKS...WMG EYE IS EMBEDDED IN AND SURROUNDED BY CDG WHICH YIELDS A
DT=7.5 AFTER PLUS 1.0 IS ADDED FOR AN EYE ADJUSTMENT. THE DVORAK TECHNIQUE
MAKES NO ALLOWANCE FOR AN EYE EMBEDDED SO DEEPLY (ABOUT 1.5 DEGREES) IN
CLOUD TOPS AS COLD AS CDG SO THE DT IS DISCOUNTED. ADT V8.1.4 CONTINUES
TO REPORT CURRENT INTENSITIES OF 8.0. FT IS BASED ON MET.

I. ADDL POSITIONS

NIL

...MCCARTHY
Click to expand...

Extremely impressive to see a cyclone maintain 8.0 for as long as Haiyan did.
 
In a case like this its probably best to consider the dvorak numbers as "offscale high". Regardless of those numbers, the satellite appearance is better than any I have ever seen, and cloud tops reached their coldest just as(maybe a tad before) the eyewall was coming onshore just south of Guiuan. So you have possibly the strongest eyewall in a very long time... hitting land!
 
Offscale, you say?

y6z.gif


Incredible view of the mesovortices earlier yesterday.

131106-07_coms1_vis_haiyan_eye_anim.gif
 
I'm a total noob when it comes to a lot of tropical stuff, including rating TC strength based on the Dvorak scale. However, my understanding is that the Dvorak number is basically read off of IR satellite. I think there is a grayscale color table that is applied to brightness temperatures from IR satellite. So a meteorologist looks for the coldest value to get a number for the Dvorak scale. Am I in the ballpark on that?
 
It's actually a method for deriving intensity from appearance, basically. Tropical cyclones of a given intensity tend to have similar visual/IR patterns, so the Dvorak technique essentially assesses the satellite appearance and uses that to derive an expected intensity. Among the more relevant factors for Haiyan are/were that the eye was embedded in a very thick CDO, it was extremely well-structured and symmetrical, and the temp contrast between the eye and the surrounding cloud tops was very large, hence the chart-topping T-numbers.

This graphic gives you an idea of how the visible patterns are assessed:

DvorakCDP1973.png


Edit: If you're interested, it looks like this training course does a nice job of covering the technique:

http://rammb.cira.colostate.edu/visit/video/dvorak/player.html
 
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Yeah, it sounds very bad. I also saw a report that two or more military trucks were swept away by the surge, killing all but two of the soldiers onboard. I don't know that it's been confirmed, so hopefully it's unsubstantiated. There was also a rumor floating around of two chasers killed in Tacloban, but I've not seen anything resembling an official source so I'm assuming it's a baseless rumor at this point. Not unusual for a lot of misinformation to come out after disasters like this.

I'm not sure which chasers you're talking about, but Josh Morgerman & co. were in what appeared to be a large, well-built hotel that he said was ~30ft. ASL. Not sure where Jim Edds was located. Either way, hopefully they're okay. I'm sure they've had more of an experience than they'd hoped for. I think it'll probably be a while before we hear from them considering the massive devastation, unless one of the news organizations can get in touch with them for footage, interviews, etc.

Edit: Uh.. I hope Jim Edds moved inland before Haiyan struck. Just looked through his tweets and he said he was out at the point, essentially on the beach (GPS is off obviously):

BYfc-_0CcAEDwTq.jpg
 
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Jim Edds is okay as well thankfully, TWC was in touch with him. Absolutely terrible death toll though, and unfortunately it will likely continue to rise.

@twc_hurricane: Just spoke with @ExtremeStorms(Jim Edds) in Tacloban. "They need to park a ship off the coast. Relief is needed here. Now."
 
Good news they are OK. It would take some brass beach balls to stick it out near the waterline.

There are enough substantial structures there for someone with good chase experience to survive. Now all you have to worry about is disease and getting out.

W.
 
As unfortunately expected, the news continues to become even more terrible. Officials are now saying as many as 10,000 people may have died in Tacloban alone. I've not heard virtually anything from Eastern Samar yet, which was likely the hardest hit area. Frankly I wouldn't be surprised if some of those villages no longer exist.

http://www.usatoday.com/story/news/world/2013/11/09/typhoon-haiyan-philippines-vietnam/3483099/

It's hard to even comprehend that magnitude of suffering and loss of life.
 
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