ATL: KATIA - Post Tropical - Discussion

[KWT]

Sharp motion to the NNW by 216hrs and weakening quickly as well...

[Aric Dunn]

Now thats a weird twist.. notice the ridging that was building north of at 192 hours.. 216 its all gone not even a trace.. with no trough either.. very weird.. that does not look right either..

[Jevo]

So here's what I take away from this Euro..

Gets a little better grasp on the ridge till about 144/168... The same place the GFS started going goofy.. Im not sure if the 280 motion to 025 is realistic yet in 24 hours at the end of the run

ok back to work for me.. Ill be lurking

18Z gfs is on the clock

[Aric Dunn]

Then at 240 already turning NE.. yeah.. its the magical world of vanishing ridges and troughs.. lol

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


clearly before the turn after 192 hours it bent to the wsw with pretty strong ridging then all of a sudden it was moving N ??? not believable at all.

[stewart715]

Then at 240 already turning NE.. yeah.. its the magical world of vanishing ridges and troughs.. lol

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


clearly before the turn after 192 hours it bent to the wsw with pretty strong ridging then all of a sudden it was moving N ??? not believable at all.

I'm having trouble having confidence in the hard NE turn at 240.

[gatorcane]

Then at 240 already turning NE.. yeah.. its the magical world of vanishing ridges and troughs.. lol

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


clearly before the turn after 192 hours it bent to the wsw with pretty strong ridging then all of a sudden it was moving N ??? not believable at all.

yeah but we are talking 192 hours+, models are not reliable in this range, not even the Euro, so I do't trust that NE hook from nowhere yet either.

[fci]

12z Euro +192

................ >>@#$@#$%@#$%@#$!@

[img]http://img695.imageshack.us/img695/7757/12zeurotropical500mbslp.if[/i\g]

Uploaded with [url=http://imageshack.us]ImageShackus[/ul]

let me add.....!!!)(%(^*$*^&$*^*(^*^ !!!!!!!!!!!!

and *^*($(%()@)%^*&(&)

well that should be a interesting track to take.. its also similar to IKE ... a little

VERY similar:


Uploaded with ImageShack.us

[SouthFloridawx]

So here's what I take away from this Euro..
Gets a little better grasp on the ridge till about 144/168... The same place the GFS started going goofy.. Im not sure if the 280 motion to 025 is realistic yet in 24 hours at the end of the run
ok back to work for me.. Ill be lurking
18Z gfs is on the clock

[SEASON_CANCELED]

I really do not believe this will be a gulf of mexico story. Maybe its just because the lattitude gain.

[otowntiger]

Euro says: "Psych!!! You thought I was really sending Katia your way. Ha!"

[gatorcane]

Yeah I see that WSW bend at the end then a sudden NNE movement.

But kindaof IKE-like....still what a BIG shift west from the 00Z Euro...

[stewart715]

2PM models westward movement. I have zero confidence in late cycle GFS.

[Jevo]

So here's what I take away from this Euro..
Gets a little better grasp on the ridge till about 144/168... The same place the GFS started going goofy.. Im not sure if the 280 motion to 025 is realistic yet in 24 hours at the end of the run
ok back to work for me.. Ill be lurking
18Z gfs is on the clock

http://img705.imageshack.us/img705/6559 ... trough.png

I was looking at that... The ridge dives from Upper NY/Canada into the Mid Atlantic in a period of 24 hous at the end of the run there.. I still think there are some unknowns at the end of the GFS and Euro runs.... the 5pm from the NHC is going to be an interesting discussion

[otowntiger]

[quote="stewart715"]2PM models westward movement. I have zero confidence in late cycle GFS.

Not much of a shift that I detect. At least not monumental by any means.

[stewart715]

2PM models westward movement. I have zero confidence in late cycle GFS.

Not much of a shift that I detect. At least not monumental by any means.

GFS mean shifted roughly 5 degrees south. Still early though, I'm sensing this will be much more drastic this time tomorrow

[SEASON_CANCELED]

NHC should just kick the can till Fridays runs. No way to say for sure that ridging appears, or even disappears like that. too much unknowns.

[SouthFloridawx]

Still looking kind of like a recurve, but if you look at the intensity of the trough, equally the ridge to the SE is fairly strong as well. If that system behind Katia that some of the models show actually forms, then we won't be having to watch Katia... We'll need to watch out for, "Maria".

[otowntiger]

So here's what I take away from this Euro..
Gets a little better grasp on the ridge till about 144/168... The same place the GFS started going goofy.. Im not sure if the 280 motion to 025 is realistic yet in 24 hours at the end of the run
ok back to work for me.. Ill be lurking
18Z gfs is on the clock

I was looking at that... The ridge dives from Upper NY/Canada into the Mid Atlantic in a period of 24 hous at the end of the run there.. I still think there are some unknowns at the end of the GFS and Euro runs.... the 5pm from the NHC is going to be an interesting discussion

What we can take away from this is that the NHC will probably not shift at all since it appears that even after all the kooky twists and turns that the Euro just spit out the storm ends up where it did in previous runs: Heading fast and furious for Greenland!

[WxGuy1]

2PM models westward movement. I have zero confidence in late cycle GFS.

Just for clarification, it looks like all of those are 12z model runs (e.g. starting at 8 a.m. EDT). The "interpolated to 2 p.m." means that they took the 12z model runs and looked at the 6 hours forecasts. In other words, those aren't "2 pm models" as much as they are the 12z / 8 am models that start at the 6 hour forecast (which itself is valid at 2 pm EDT).

The 12z GFS and ECMWF still show a sizeable upper-tropospheric trough in the eastern U.S. in 7-8 days that acts to provide southwesterly flow aloft over the northwestern Atlantic. This explains why the models end up either recurving Katia or forcing it to a much higher latitude (impacting maritime Canada?), and it may provide some stronger vertical wind shear over Katia. The intensity of this trough in terms of the amount of mid-level cold air associated with it / the extent of the low heights / the strength of the winds has varied from run to run and model to model, though they've all shown a trough there (500 miles to the east or west).

Of course, we still are looking out 6-8 days, but the general consensus has not changed much in the past couple of days, with both of the primary global models showing a large trough in the eastern U.S. that is forecast to prevent a U.S. landfall.

Forecasts may change, and this isn't saying that it's impossible that Katia could impact the U.S. However, it continues to look quite unlikely (again, not impossible, but unlikely), and that hasn't changed in the past couple of days. Minor shifts east or west probably won't make much difference as long as that large trough that the ECMWF and GFS are forecasting does end up verifying.

[chris_fit]

I'm not seeing any major shifts.... In all likely hood, this will re-curve and Bermuda is the only ? mark.