ATL: IGOR - Ex Hurricane - Discussion

[KWT]

Nah it won't be a category-5 before then neo but obviously if it was to become even more impressive according to Dvorak then it may well get a special upgrade like it did today...who knows!

[KatDaddy]

Igor looks to be a CAT 5. Amazing satellite images.....thankfully out to sea.

[KWT]

I was tempted to mention the possibility of an annular hurricane too, obviously is not annular yet but maybe later in its life. I'm sorry I know the annular word is controversial on this board

Its funny you mention that because it just developed a big ole blow-up to the SE of the core, sort of like a wart on Igor!

[Macrocane]

Look at that closed ring of deep convection around the eye, it's amazing!

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[hurricaneCW]

It's very rare for an Atlantic hurricane to look like that, except in 2005 which was an insane season. I'd go with 155 mph next advisory and maybe even 160 mph although there's not quite enough evidence to support a Cat 5 upgrade.

[ozonepete]

That ring is tightening in on the center. Could be an eyewall rep.

[Just Joshing You]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 12 SEP 2010 Time : 221500 UTC
Lat : 17:39:21 N Lon : 46:47:09 W


CI# /Pressure/ Vmax
6.6 / 934.2mb/129.6kt


Final T# Adj T# Raw T#
6.6 6.7 6.7

Latitude bias adjustment to MSLP : +2.0mb

Estimated radius of max. wind based on IR : 25 km

Center Temp : +16.7C Cloud Region Temp : -70.4C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

****************************************************

[johngaltfla]

That is one of the most impressive hurricanes I've seen of its caliber in the Eastern Atlantic in my lifetime. Absolutely perfect presentation. God Help us if it doesn't recurve.

[CrazyC83]

I'd put it at 130 kt given the data available. I wonder if some agencies will start getting out some T7.0 readings?

[ozonepete]

BTW, Isabel didn't go annular until after it did an eyewall replacement and became a cat 5.

[HURAKAN]

Latest

[ozonepete]

Awesome. That's a LOT of power.

[ozonepete]

Looks like a classic ERC is underway.

[Battlebrick]

Looks like a classic ERC is underway.

I don't see it.

[lester]

Looks like a classic ERC is underway.

Haven't seen any indication of one yet..

[ozonepete]

Looks like a classic ERC is underway.

I don't see it.

Look at an IR satellite loop:
http://www.ssd.noaa.gov/goes/flt/t1/flash-avn.html

The wide ring of red colors that has developed around the center is now filling in closer and closer to the eye. That is a ring of convection that is becoming the new eyewall. Here's what happens:

Often, especially in the strongest hurricanes, a new ring of thunderstorms will start to develop around the outside of the original eyewall, and as this outer ring becomes complete, the inner eyewall erodes and then dissipates, leaving a new, larger eye. While the reasons why this phenomenon occurs are still not well understood by meteorologists, it is easier to understand why the inner eyewall dissipates. As the new, outer eyewall encircles the inner one, it starts to ingest the incoming moist air that the inner circle of thunderstorms needs to maintain itself, thus cutting off the inner eyewall's fuel source. In addition, Professor Lee Grenci of Penn State has postulated that the dynamically induced subsidence in the air out-flowing from the tops of the thunderstorms of the outer eyewall into the area of the inside eyewall also probably hastens the demise of the inner eyewall, by introducing dry air into the inner eyewall thunderstorms. In any event, as a hurricane undergoes this process, it will obviously weaken, as the new, larger eyewall experiences a decrease in tangential wind speed as angular momentum is conserved.

[O Town]

Beautiful looking storm. Eyewall looking strong now, no ERC yet.

[fasterdisaster]

Looks like a classic ERC is underway.

I don't see it.

Look at an IR satellite loop:
http://www.ssd.noaa.gov/goes/flt/t1/flash-avn.html

The wide ring of red colors that has developed around the center is now filling in closer and closer to the eye. That is a ring of convection that is becoming the new eyewall. Here's what happens:

Often, especially in the strongest hurricanes, a new ring of thunderstorms will start to develop around the outside of the original eyewall, and as this outer ring becomes complete, the inner eyewall erodes and then dissipates, leaving a new, larger eye. While the reasons why this phenomenon occurs are still not well understood by meteorologists, it is easier to understand why the inner eyewall dissipates. As the new, outer eyewall encircles the inner one, it starts to ingest the incoming moist air that the inner circle of thunderstorms needs to maintain itself, thus cutting off the inner eyewall's fuel source. In addition, Professor Lee Grenci of Penn State has postulated that the dynamically induced subsidence in the air out-flowing from the tops of the thunderstorms of the outer eyewall into the area of the inside eyewall also probably hastens the demise of the inner eyewall, by introducing dry air into the inner eyewall thunderstorms. In any event, as a hurricane undergoes this process, it will obviously weaken, as the new, larger eyewall experiences a decrease in tangential wind speed as angular momentum is conserved.

We know what an EWRC is, we just don't think one is happening. Just because convection increases around the eye doesn't mean there's a second eyewall. If anything it means Igor's still intensifying and is a while away from any EWRC.

[HURAKAN]

Latest

[CrazyC83]

Now we wait for the numbers. What will the other agencies say?

ADT supports an intensity of 130 kt right now, which is also my guess for the current intensity (pressure 937mb).