ATL: KATIA - Post Tropical - Discussion

[Jevo]

Current Steering

[img]http://40.imageshack.us/img40/3403/wg8dlm2.gif[/

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Jevo, can you explain what a newbie might need to recognize on the current stearing and Katia? Thank you very much.

In newbie speak storms usually follow the path of least resistance.. So you have the large circular shapes which are ridges (or high pressure) then you have straight lines that usually will curve or dip down known as troughs or jets.. they are known to punch a hole or push away the ridges to create a weakness for the storm to travel along. Then you have the smallers swirles that are upper level lows or storms that we have right now like Katia (but thats a different story)

so basically when you look at a steering current map imagine the storm as a boat that follows the current and flows and it becomes easier.. Heh I hope that made sense I tried to explain it the way it was explained to me about 10 years back... If someone wants to follow behind me and patch up any errors feel free..

[KWT]

Hmmm NHC not totally commiting to the bend back, instead just holding it on the straight NW more or less.

[supercane]

Latest microwave:

[Jevo]

Hmmm NHC not totally commiting to the bend back, instead just holding it on the straight NW more or less.

I dont think we started seeing those bends until +144 / +168 which would be outside of their current 5 day forecast package

[cycloneye]

Latest microwave:
http://img97.imageshack.us/img97/2015/2 ... 1h1deg.jpg

Almost a closed eyewall on that image.

[gatorcane]

ECMWF operational, 12Z loop. Notice the big bend to the west:
http://moe.met.fsu.edu/cgi-bin/ecmwf-op ... =Animation

ECMWF ensembles, 12 loop, in agreement with the operational:
http://moe.met.fsu.edu/cgi-bin/ecmwf-en ... =Animation

[WeatherLovingDoc]

Thanks for your response, HenkL

[Jevo]

18Z GFS Initialized (24 hour plots)

[meriland23]

ECMWF operational, 12Z loop. Notice the big bend to the west:
http://moe.met.fsu.edu/cgi-bin/ecmwf-op ... =Animation

ECMWF ensembles, 12 loop, in agreement with the operational:
http://moe.met.fsu.edu/cgi-bin/ecmwf-en ... =Animation

And this is the euro correct? From what I understand, the NHC uses ecmwf as a major factor in their updates, but that is just here say. If that is the case, I suppose the NHC could possibly change up their PP soon, probably afer around 70w. Very interesting model run there, is that most recent?

[gatorcane]

ECMWF operational, 12Z loop. Notice the big bend to the west:
http://moe.met.fsu.edu/cgi-bin/ecmwf-op ... =Animation

ECMWF ensembles, 12 loop, in agreement with the operational:
http://moe.met.fsu.edu/cgi-bin/ecmwf-en ... =Animation

And this is the euro correct? From what I understand, the NHC uses ecmwf as a major factor in their updates, but that is just here say. If that is the case, I suppose the NHC could possibly change up their PP soon, probably afer around 70w. Very interesting model run there, is that most recent?

Yes, but the bend west the ECMWF (also known as the Euro) shows happens after the 5-day forecast point so they are not mentioning it right now.

Plus I am sure they like the rest of us want to see a few more runs to see if there is any consistency there or not.

It is interesting to note that two days ago, the Euro was showing a similar (a little more north though) solution....

Needless to say the ECMWF is not very consistent in the long-range on where it thinks Katia will end up. The GFS has been much more consistent but it has been known to break down ridges too quickly in the long-range so we'll see.

[Jevo]

18z GFS +24



18Z GFS +48

[meriland23]

In GFS 18z, is the model currently running and not available past 69 hrs or is my computer being funky?

[Jevo]

18z GFS +72

[ckiggins]

Can someone explain to another newbie the complete differences in tracks?

I have been watching the following on Ryan Maue's site:

http://coaps.fsu.edu/~maue/tropical/plots/uv900atl_anim_16.html
http://coaps.fsu.edu/~maue/tropical/plots/ec850uva.html

The two models show incredibly different positions of the storm at 8 days. At what point do these become more accurate? 5 days out?

[SouthFLTropics]

Looking awfully troughy out there at 72 hours...Wonder if it lifts out and the high builds in or if Katia gets swept out to sea. The suspense is killing. TNT says they know drama...I say that S2K knows drama!!!

SFT

[Macrocane]

Katia is looking really good right now, too bad that there won't be more visibles for several hours, it could be already a hurricane IMO. They could issue a special advisory but it is not affecting land so possibly they will wait until the next normal advisory.

[Jevo]

12z GFS +96

[gatorcane]

Looks like the 18Z is very similar to the 12Z through 114 hours.....

[Jevo]

12z GFS +120

[SouthFLTropics]

Is it just me or does this run of the GFS seem to be taking forever to process???

SFT