ATL: FOUR - Remnants - Discussion

[Blinhart]

i been reading we could see 94l disactive by 5am or 8am or 2pm thur

Yet here we have TD4

[Nimbus]

The convection persisted long enough for this to become TD 4 but infrared imagery shows a warming cloud top trend with an eastern band back in the drier air.

Could be just a diurnal intensity fluctuation but Hammy said the environment was deteriorating so guess we will have to wait and check in later.

[GCANE]

Even though SAL is on its heels, IMHO this can still keep going.
These pouches have a tendency to protect itself from SAL.
Its vort column is well stacked from 850mb to 500mb.
200mb PV is in the clear and its moving into an anticyclone which will maintin the vort structure.
Very nice symmetrical cirrus outflow pattern.
Still see a strong infeed of low-level moist air from the south per MIMIC-TPW.

[ronjon]

Looking pretty darn healthy on SAT this am. Notice the fingering of cirrus that is almost symmetrical along the outer edges of the convection - that's a sign of an anti-cyclone sitting a top the TD at 200 mb.

http://www.ssd.noaa.gov/PS/TROP/floaters/04L/imagery/rb_lalo-animated.gif

[gfsperpendicular]

Looking pretty darn healthy on SAT this am. Notice the fingering of cirrus that is almost symmetrical along the outer edges of the convection - that's a sign of an anti-cyclone sitting a top the TD at 200 mb.

http://www.ssd.noaa.gov/PS/TROP/floaters/04L/imagery/rb_lalo-animated.gif

It's even popping shallow convection to it's east...maybe TD4 has more time than we think...

[wxman57]

Looks extremely disorganized, to me. Barely qualifies for a TD. I think that the NHC is being generous in calling it one. Don't let the convection with semi-impressive outflow in the IR satellite imagery fool you, the center isn't under there. Visible satellite tells the real story. Circulation is very weak and east of the convection. Not much threat to the Caribbean or anywhere else.

[SouthDadeFish]

A recent WindSat pass doesn't show anything remarkable about the low-level structure. It still appears as if the low-level center is on the eastern edge of the convective mass:

[RL3AO]

The slow trade winds helped it develop, but now the stronger mid-level winds on the leading edge of the SAL are shearing it. Wouldn't be surprised if this is dead by this evening.

[RL3AO]

Here's a good example of shear maps/plots not showing the situation correctly. The 200mb-850mb vector difference and 500mb-850mb difference is shown in the table on the right. But, the storm killing shear (and dry air) is between 600 and 800mb. It doesn't show up in the typical shear map products.

[tropicwatch]

The slow trade winds helped it develop, but now the stronger mid-level winds on the leading edge of the SAL are shearing it. Wouldn't be surprised if this is dead by this evening.

NHC has it maintaining TD strength throughout the forecast period.

[tolakram]

SLIDER visible

http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=19298&y=8178&z=4&im=12&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&p%5B0%5D=2&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&s=rammb-slider

[wxman57]

The slow trade winds helped it develop, but now the stronger mid-level winds on the leading edge of the SAL are shearing it. Wouldn't be surprised if this is dead by this evening.

NHC has it maintaining TD strength throughout the forecast period.

No, they weaken it to a remnant low this weekend.

INIT 06/0900Z 13.2N 40.0W 25 KT 30 MPH
12H 06/1800Z 14.0N 42.5W 30 KT 35 MPH
24H 07/0600Z 15.0N 46.2W 30 KT 35 MPH
36H 07/1800Z 16.3N 50.0W 30 KT 35 MPH
48H 08/0600Z 17.5N 53.5W 25 KT 30 MPH
72H 09/0600Z 20.5N 59.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 10/0600Z 23.0N 65.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 11/0600Z...DISSIPATED

[tropicwatch]

I was looking at their forecast cone. Never mind I see it on Sunday.

[Alyono]

woudn't be surprised if it is dead now or soon

These types of systems often lose their circulation about 12 to 18 hours after an impressive convective burst. Once the convection collapses, there is a large amount of surface divergence, which can quickly open up a small, weak circulation. Happened with the TDs in 2000 an 2003 in June

[Aric Dunn]

Sal has finally caught up to it. Not much chance left now...

[Aric Dunn]

bit of an outflow boundary on the NW side not a good sign especially being such a small system.

[Gustywind]

DATE/TIME LAT LON CLASSIFICATION STORM
06/1145 UTC 13.3N 41.5W T1.5/1.5 04L
06/0545 UTC 13.2N 39.2W T1.5/1.5 04L
05/2345 UTC 12.6N 37.6W T1.5/1.5 94L
05/1745 UTC 12.1N 36.8W T1.5/1.5 94L
05/1145 UTC 12.0N 35.8W T1.0/1.0 94L
05/0545 UTC 10.8N 35.4W T1.0/1.0 94L
04/1145 UTC 10.0N 33.4W TOO WEAK 94L
04/0545 UTC 9.5N 34.0W T1.0/1.0 94L

[Gustywind]

bit of an outflow boundary on the NW side not a good sign especially being such a small system.

Hi Aric glad to see you again. What are your latest thoughts on TD 4 concerning a possible impact on the Leewards and Northern Leewards?
Thanks.
Gustywind

[Aric Dunn]

bit of an outflow boundary on the NW side not a good sign especially being such a small system.

Hi Aric glad to see you again. What are your latest thoughts on TD 4 concerning a possible impact on the Leewards and Northern Leewards?
Thanks.
Gustywind

little to none should move well north and be quite weak.

[NDG]

Is it gone already?