ATL: KATIA - Post Tropical - Discussion

[SouthFloridawx]

[gatorcane]

GFS spaghetti models definitely bring this much closer to the US than before. Difference is being split between the US and Bermuda.

http://tinyurl.com/3hvplms

A couple of those tracks are through the Bahamas and near Florida now also...

[dwsqos2]

The HWRF is such a terrible intensity model.

[Aric Dunn]

GFS spaghetti models definitely bring this much closer to the US than before. Difference is being split between the US and Bermuda.

http://tinyurl.com/3hvplms

very interesting .. a few of them go across Florida and the SE.

[Aric Dunn]

Euro rolling in ...

[SouthFloridawx]

Here is the 6Z GFS ensemble. We'll see what the difference is between the runs.

[Aric Dunn]

think the euro is also out to lunch.. in 24 hrs its kills like all the ridging over the us and north of it. for no reason.. lol and katia move from its present position straight NW ... dont think so sorry ... lol

http://raleighwx.americanwx.com/models/ ... _loop.html

[Aric Dunn]

no real change in the GFDL either.

[gatorcane]

It's been a while since I have seen a nice Bermuda High setup and ridging along the Eastern Seaboard of the U.S.

There always seems to be a trough on the East Coast.

Models aren't wanting to change the long-wave pattern anytime soon.

[Aric Dunn]

It's been a while since I have seen a nice Bermuda High setup and ridging along the Eastern Seaboard of the U.S.

There always seems to be a trough on the East Coast.

Models aren't wanting to change the long-wave pattern anytime soon.

yeah but things will change ... being all the models finally kill the heat ridge in a few days so after all these systems clear out we might see it set up finally

[Blown Away]

[img]http://img820.imageshack.us/img820/969/gefsspagatlantic192mslp.gif[/ig]

Lol, what is that? Looks like 1st grade art class?

[Aric Dunn]

seems to be quite a bit of ridging building back in north of her with the euro 5 days ...

http://raleighwx.americanwx.com/models/ ... _loop.html

[SouthFloridawx]

[img]http://img820.imageshack.us/img820/969/gefsspagatlantic192mslp.gif

Lol, what is that? Looks like 1st grade art class?

Why thank you, I drew it myself ; )

[gatorcane]

seems to be quite a bit of ridging building back in north of her with the euro 5 days ...

http://raleighwx.americanwx.com/models/ ... _loop.html

Yeah how is it possible that Katia plows right through that? Doesn't seem right, seems like she should bend due west?

Maybe that is why we have seen a few runs of the Euro bending due west towards the Bahamas...

[stewart715]

Lol, what is that? Looks like 1st grade art class?

COLORSSSSS

[Jevo]

12Z Euro +120



Uploaded with ImageShack.us

[Aric Dunn]

seems to be quite a bit of ridging building back in north of her with the euro 5 days ...

http://raleighwx.americanwx.com/models/ ... _loop.html

Yeah how is it possible that Katia plows right through that? Doesn't seem right, seems like she should bend due west?

Maybe that is why we have seen a few runs of the Euro bending due west towards the Bahamas...

yeah besides all that part of it.. the beginning of the run she plows through the ridging.. well actually it all just disappears after initialization. I think that is the big problem its having its send it NW from right now to 120 how..

[SouthFloridawx]

It's the ensemble track plots for GFS. As explained below:

The GFS Ensemble System (GEFS) consists of 20 statistically independent perturbations plus one control member which are run 4 times per day (initialized at 00, 06, 12, and 18 UTC). As of the major upgrade in February 2010, each ensemble member is run with 28 vertical levels and a triangular truncation of 190 waves (T190) in the horizontal (this gives an effective grid point spacing of ~80 km). After 180-hr, the ensemble members are truncated to T126, which degrades their performance and makes it difficult for the tracker to follow tropical cyclones. In comparison, the operational GFS is run with 64 vertical levels and T574 in the horizontal (an effective grid point spacing of ~27 km). After 192-hr, the operational GFS is run at T190 through 384 hours (16 days). Initial conditions come from the Gridpoint Statistical Interpolation (GSI) global data assimilation system (GDAS). This system incorporates a 3D-VAR method to continuously update the background fields used for the initial condition.

The control member uses these initial conditions directly, while the perturbed members use an initial condition which has been obtained using an Ensemble Transform Bred Vector (ETBV) method that is designed to pick out the fastest growing modes in the model (with the hope that these simulate the fastest growing sources of uncertainty in the atmosphere). These perturbations are also subjected to stochastic physics perturbations. Note that this perturbation method is generally best suited for the extra tropics -- no special perturbations are conducted specific to individual tropical cyclones.

http://www.ral.ucar.edu/guidance/guide/gfs/

Link to view the models:

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller?prevPage=Model&MainPage=index&model=GEFS-SPAG&area=ATLANTIC&areaDesc=Atlantic+region&page=Model&prevModel=&prevArea=ATLANTIC&currKey=model&prevKey=model&cat=MODEL+GUIDANCE

[gatorcane]

Ahh. now she has made a big turn on the 12Z ECMWF, bending W to even WSW....that makes more sense

Look at that big 500MB ridge overtop of her now...wonder how far west she goes this time???

[Aric Dunn]

There is the turn ! I think we need to give a little more credence to a possible US threat now. that more models are turning west.

http://raleighwx.americanwx.com/models/ ... _loop.html