ATL: KATIA - Post Tropical - Discussion

[otowntiger]

wow really.. CMC large ridging even more than the 00z run!!! west turn and likely after that straight west to florida.

12z
http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation

Yeah Aric, I see that, it seems that weakness is closing up pretty quickly there and a huge ridge is moving in from the United States west towards the Western Atlantic. Seems like it would head into the Bahamas and Florida after that.

The CMC is usually good with synoptics, just need the GFS or ECMWF to jump on board before I start believing these westward shifts.

well to be honest. the gfs did shift west a lot and I bet when the ensembles come out that more take to the west again like the 00z and 6z ..

watching the spaghetti plots to update..

I don't know Aric. Looking at those models I still don't quite see the synoptics that would send the storm west for sure. I still see a big weakness (albeit closing) that would allow Katia to punch through and head back north and northeast. In tha one model graphic she has gained quite a bit of lattitude by the end. Now if you are looking at trends then yes that would be a good point. We would need to see if the trend continued to push west until the system has no choice but to ram us (CONUS) from the east. We don't know if that trend will continue. For all we know the weakness/trough will start to strengthen again with each successive run. It does make for excitement (good and bad) not knowing for sure what she will do.

Just my amatuer 2 cents. Take this all with a grain of salt. "....S2K disclaimer et.al.....blah, blah, blah..."

[Aric Dunn]

There certainly is a big surface ridge. What about the 500mb ridging. Still a pretty healthy trough eroding the ridging.
[img]http://img69.imageshack.us/img69/9522/595100.gif[img]

right but its the ridging that is sliding off the east coast. the atlantics erodes but the other ridge begins to fill in as that trough clearly lifts out ..

It's going to be interesting to see the actual evolution of those features and to see the eventual track of Katia.

for sure. this is the fun part

[Jevo]

Yeah, CMC and NOGAPS seem to be telling us not to write off Katia as a recurve just yet.......

as well as the GFDL 6z had a slight westward bend at end of run. and now the GFS shift a lot to the west. so far today seems a trend west.. from yesterday

Well, I am admittedly selfish and concerned about a possible similarity to a certain storm with an "A" name; and a possible effect where I live in South/Central Florida.
Of course, I worry about further up the coast still reeling from Irene, but I look selfishly at where I live first.
Just being honest............

Don't let his smile and cherub like demeanor fool you... If Dr. sheets hears you comparing Katia to Andrew 10 days out he will find you and make you scream uncle

[Jevo]

for sure. this is the fun part

Queues the Monday Night Football music

Are you ready for some Eurooooooooo

12z firing up

[poof121]

CMC 12Z, 144 HR



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Looks like the two highs may end up bridging at the end of the CMC.

[SouthFLTropics]

Yeah, CMC and NOGAPS seem to be telling us not to write off Katia as a recurve just yet.......

as well as the GFDL 6z had a slight westward bend at end of run. and now the GFS shift a lot to the west. so far today seems a trend west.. from yesterday

Well, I am admittedly selfish and concerned about a possible similarity to a certain storm with an "A" name; and a possible effect where I live in South/Central Florida.
Of course, I worry about further up the coast still reeling from Irene, but I look selfishly at where I live first.
Just being honest............

I assume you are talking about a certain "A" name that occurred in 1992...and yes, the potential track does look somewhat the same. The question still is will the end result be the same. The jury is still out on this one. We have a long way to go.

SFT

[Shuriken]

If Katia can close that eye off, could she rapidly intensify or even bomb out?

Probably. (Hugo was a cat-5 east of the Lesser Antilles.)

[Aric Dunn]

no real change in the hwrf. gfdl not out yet.

sorry take that backk.. HWRF now turns back wnw..

[SouthFLTropics]

no real change in the hwrf. gfdl not out yet.

Still bending west at the end???

[Aric Dunn]

GFDL is just about the same as the previous one.

left side of guidance...

[Jevo]

12z Euro (ECMWF) Initialized



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12z Euro +24



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[Jevo]

12z Euro +48



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[KWT]

Yep the models are now showing at least a brief westward bend it seems by 120hrs, will have to see how it evolves.

At least makes things more interesting...

[fci]

Still looks like it's not going to have any significant impact on the NE Caribbean, and it will probably recurve well east of the U.S.

You're not concerned with some of the models bending Katia westward at the end of their runs?

[clfenwi]

SAB's Dvorak intensity estimate remains unchanged

31/1745 UTC 14.4N 41.7W T3.5/3.5 KATIA

[alan1961]

Interesting that the tropical forecast points have
disappeared from the sat animaton loops, upgrade
to hurricane and/or track change coming?

[ouragans]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 31 AUG 2011 Time : 171500 UTC
Lat : 14:20:02 N Lon : 41:25:16 W


CI# /Pressure/ Vmax
3.9 / 993.8mb/ 63.0kt


Final T# Adj T# Raw T#
3.9 4.1 4.1

Center Temp : -48.3C Cloud Region Temp : -59.6C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

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

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 52km
- Environmental MSLP : 1015mb

Satellite Viewing Angle : 41.9 degrees

[Jevo]

12Z Euro +72



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12Z Euro +96



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[otowntiger]

Yep the models are now showing at least a brief westward bend it seems by 120hrs, will have to see how it evolves.

At least makes things more interesting...

Yes, but that west bend happens at such a high lattitude and east longitude that she would still have plenty of time to recover her re-curve plot when/if the trough catches her so she still could miss the U.S. mainland altogether and still by a wide margin.

[KWT]

Yep the models are now showing at least a brief westward bend it seems by 120hrs, will have to see how it evolves.

At least makes things more interesting...

Yes, but that west bend happens at such a high lattitude and east longitude that she would still have plenty of time to recover her re-curve plot when/if the trough catches her so she still could miss the U.S. mainland altogether and still by a wide margin.

Yep your very right, odds still rather strongly favour a recurve, however these trends do make a difference, esp for possibly NF and NS.