ATL: ISAAC - Post-Tropical - Discussion

[brunota2003]

Well, this is the first time I've used the red on an "active" map. Still small, but that's all the NHC has highlighted on their maps as 20% or greater, thus far. Expecting the red to expand tonight and tomorrow quite a bit, pending on what Isaac looks like coming off the coast of Cuba.

And thanks to those that liked my Neil photo.

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[Aric Dunn]

appears recon latest center fix is nnw of the previous one makes me back up my statement that its being pulled towards the developing convection.

[SunnyThoughts]

Here is the part of the discussion from the last update that has to do with intensity along the northern gulf coast.

After that...the shear should diminish while the cyclone
reaches open water. This should allow Isaac to gradually strengthen
into a hurricane near the Florida Keys or over the southeastern
Gulf of Mexico. The new intensity forecast is similar to the
previous forecast and is near or a little above the intensity
consensus. It should be noted that the global models are
forecasting a very favorable pattern of upper-level winds over the
northern Gulf of Mexico by 72 hr. Should this verify and should
Isaac establish an inner core...the cyclone could be significantly
stronger than currently forecast.

['CaneFreak]

Yep and backs up my statement earlier that it would get pulled away from the coast by developing convection on the north, east, and west sides...look out

appears recon latest center fix is nnw of the previous one makes me back up my statement that its being pulled towards the developing convection.

[TropicalAnalystwx13]

From the latest VDM:

L. Eye Character: Open from the north to the west
M. Eye Shape & Diameter: Circular with a diameter of 25 nautical miles (29 statute miles)

http://www.ssd.noaa.gov/PS/TROP/floater ... y/rgb0.jpg

[Recurve]

This afternoon windfield analysis from NOAA AOML/HRD. Shows wind field compiled from recon, radar, sat and buoy data, and gives total integrated kinetic enery and destructive potential rating (now 0 from winds, 1 from waves,water.)

The earlier 50-knot winds aren't there after the crossing it seems. But a wide area of storm winds.



Uploaded with ImageShack.us

As storm approaches your area, if you really want to know where winds are and get the best picture of actual analyzed windfield, keep an eye on these products.

ftp://ftp.aoml.noaa.gov/hrd/pub/hwind/Operational/2012/AL092012/

[Janie2006]

I've heard many people over the years say "The water in the Gulf is so warm...a hurricane can just explode!" when in reality it can't. It doesn't matter of SSTs are exceedingly warm or not. If the atmospheric conditions aren't right (and it lacks the structure) the storm simply cannot intensify to any great extent, to say nothing of RI. That being said, that *may not* be the case here.

Going along with NHC's estimation, a Cat 2 certainly isn't out of the realm of possibility here by any means. We've seen many storms get their act together in a hurry.

[Meteorcane]

that wind field will be approaching South Florida quite soon, so I would not be surprised to have sustained T.S. winds in Miami-Dade.

[brunota2003]

Now that's something to chew on. If it gets under that convection and closes itself off, things just might get rather interesting...

Also, saw on twitter from Mike Thesis residents in the Keys are parking their vehicles up on the elevated roads leading to bridges to avoid storm surge.

[cheezyWXguy]

If it were to somehow bomb out would that make it go poleward more as other storms have?

No, this is going to be steered by large scale factors such as the high to the north and the trough lifting out of the east coast, and smaller scale factors like the vort max to its west, south of western cuba. The concept of a storm moving more poleward as it increases in strength is more important in the deep tropics like in the MDR and the Caribbean.

[Frank P]

I've heard many people over the years say "The water in the Gulf is so warm...a hurricane can just explode!" when in reality it can't. It doesn't matter of SSTs are exceedingly warm or not. If the atmospheric conditions aren't right (and it lacks the structure) the storm simply cannot intensify to any great extent, to say nothing of RI. That being said, that *may not* be the case here.

Going along with NHC's estimation, a Cat 2 certainly isn't out of the realm of possibility here by any means. We've seen many storms get their act together in a hurry.

Also size of wind field play a hugh factor in surge heights..

[Aric Dunn]

If it were to somehow bomb out would that make it go poleward more as other storms have?

No, this is going to be steered by large scale factors such as the high to the north and the trough lifting out of the east coast, and smaller scale factors like the vort max to its west, south of western cuba. The concept of a storm moving more poleward as it increases in strength is more important in the deep tropics like in the MDR and the Caribbean.

no, that occurs not matter what latitude.

[Blinhart]

If it were to somehow bomb out would that make it go poleward more as other storms have?

No, this is going to be steered by large scale factors such as the high to the north and the trough lifting out of the east coast, and smaller scale factors like the vort max to its west, south of western cuba. The concept of a storm moving more poleward as it increases in strength is more important in the deep tropics like in the MDR and the Caribbean.

Also we have seen plenty of storms that get to Cat 3 or Cat 4 and continue moving W in the Caribbean, so you can never say that the strength will make it go more poleward. It takes all the different dynamics around to cause the storm to move a certain direction.

Right now I just don't see enough dynamics to cause this storm to move so fast North when he gets into the GoM.

[Recurve]

Aric, isn't that tug poleward part of the beta effect in the BAMs?

[meriland23]

my personal opinion is this will be a low cat 3, IMO

[Blinhart]

My opinion is that this could slow down in the GoM, but not stall out and get close to Cat 4.

[Aric Dunn]

:uarrow: Aric, isn't that tug poleward part of the beta effect in the BAMs?

its a pressure/rotational effect. also depends of course how much steering influence you have. strong ridging you get the wobble wars weak steering ends up being a steady curve.

[TropicalAnalystwx13]

An intense hurricane does not always have to move more poleward. If the ridge is intense enough, it will force the cyclone on a westward track. This was shown by Hurricanes Dean and Felix in 2007.

[Portastorm]

An intense hurricane does not always have to move more poleward. If the ridge is intense enough, it will force the cyclone on a westward track. This was shown by Hurricanes Dean and Felix in 2007.

And Gilbert in 1988

[Aric Dunn]

An intense hurricane does not always have to move more poleward. If the ridge is intense enough, it will force the cyclone on a westward track. This was shown by Hurricanes Dean and Felix in 2007.

correct but it does not mean then tendency is not there. you can hold to small magnets together but try to stronger ones. equal and opposite. the hurricanes were still "bumping up against the ridging hence thats why we get wobble wars.. just the ridge is bigger and hurricanes are smaller essentially you can hold you brother down when hes little ( if you have one) but not when hes grown up... lol