ATL : HARVEY - Tropical Depression - Discussion

[GCANE]

GCANE, low level convergence is increasing.

Thanks Cycloneye!

I am wondering out loud if the LLC might get repositioned later under the convection.

Has been steady all morning, indicating a slow build up in core temp.

Also looks like it is gaining in altitude as well; or should I say as usual.

[tailgater]

GCANE, low level convergence is increasing.

Yep I think by tomorrow afternoon this one will start looking good at the surface and will need some recon.

[dolebot_Broward_NW]

Interesting that the curved cloud out ahead of the area of main convection has persisted as long as it has. Something must have shut off her fuel in a hurry to have the storms collapse and poof like that. I'm noting some action along that boundary. Would this serve to stabilize the atmosphere? Here when t-storms collapse like that often new ones form along that same boundary, but not sure it works in the deep tropics.

[Sanibel]

Still showing signs of weakness but I think this one will play-out stronger than the others if it doesn't crash and burn over Central America.

[Dave]

Recon for today is still a go.

[ozonepete]

Interesting that the curved cloud out ahead of the area of main convection has persisted as long as it has. Something must have shut off her fuel in a hurry to have the storms collapse and poof like that. I'm noting some action along that boundary. Would this serve to stabilize the atmosphere? Here when t-storms collapse like that often new ones form along that same boundary, but not sure it works in the deep tropics.

That's not a thunderstorm outflow boundary like we usually see. The usual ones are low-level and produced by a collapse downward of dry air which then rushes out in an arc which is a forward rushing boundary that acts like a micro or macro front that can initiate new storms, as you said.
This is a high level arc cloud that is mostly cirrus. It is a gravity wave that was left over from the high level cirrus outflow, so it will not create any new weather of its own and should dissipate soon.

[Dave]

All HDOBS, VDM's, Dropsondes, Flight Graphics. Any discussions please use the Recon Discussion thread. Thanks!



Recon Discussion Thread:

http://www.storm2k.org/phpbb2/viewtopic.php?f=59&t=111494

Opens in a seperate window.

=====================
ATLANTIC REQUIREMENTS
1. SUSPECT AREA (SOUTH OF PUERTO RICO)
FLIGHT ONE -- TEAL 70
A. 16/1800Z
B. AFXXX 01FFA INVEST
C. 16/1700Z
D. 15.0N 65.0W
E. 16/1730Z TO 16/2130Z
F. SFC TO 10,000 FT

Hasn't been cancelled yet...as of 12:15 pm edt that is.

[Dave]

Questions, comments, etc for 93L...thanks everyone!

[cycloneye]

Dave,the remark at TCPOD of SE of Bermuda mission canceled is correct?

[painkillerr]

Any comments on these?

[Dave]

Dave,the remark at TCPOD of SE of Bermuda mission canceled is correct?

Yes the TCPOD SE of Bermuda is cancelled. Double checked with Hurakan on it also.

Cycloneye, in contact with Brent and he agree's the mission SE of Bermuda that was cancelled must have been the one scheduled for today into 93L. Nothing in on hdobs yet. Unless something happens soon....see ya later today or tomorrow.

[cycloneye]

Any comments on these?

http://img812.imageshack.us/img812/5051/avnl816111200.jpg

The members are discussing about features apart from 93L at Talking Tropics forum.

[Gustywind]

Orange alert have been requiered for Guadeloupe at noon for a risk of strong showers and tstorms.

[Gustywind]

Situation is becoming a bit worrying in Guadeloupe as some floodings have begun in some localities as Pointe-A-Pitre. Heavy dowpours are spreading on us. We're continuing to follow closely the situation hoping that nothing bad occurs. I will be you more infos if anythings happens.

[tolakram]

I think it's at least plausible that some kind of LLC is trying to form.

LOOP: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... map=latlon

Overall flow is still east to west but low level motion is starting into the area of storms.

[supercane]

Recon for today is still a go.

As discussed a few posts above yours, unsure whether it is still a go, as the only flight scheduled for today was an invest of the Carribean disturbance:
000
NOUS42 KNHC 151500
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1100 AM EDT MON 15 AUGUST 2011
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 16/1100Z TO 17/1100Z AUGUST 2011
TCPOD NUMBER.....11-076

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (SOUTH OF PUERTO RICO)
FLIGHT ONE -- TEAL 70
A. 16/1800Z
B. AFXXX 01FFA INVEST
C. 16/1700Z
D. 15.0N 65.0W
E. 16/1730Z TO 16/2130Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: BEGIN 12-HRLY FIXES
AT 17/1200Z IF SYSTEM DEVELOPS.
3. REMARK: TASKING FOR SUSPECT AREA SOUTHEAST OF
BERMUDA FOR 15/1800Z AND 16/0600Z CANCELED BY
NHC AT 15/1100Z.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
JWP

And today's POD cancels the flight scheduled for 16/1800Z, although it notes it southeast of Bermuda.
000
NOUS42 KNHC 161530
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1130 AM EDT TUE 16 AUGUST 2011
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 17/1100Z TO 18/1100Z AUGUST 2011
TCPOD NUMBER.....11-077

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (SOUTH OF PUERTO RICO)
FLIGHT ONE -- TEAL 71
A. 17/1800Z
B. AFXXX 01FFA INVEST
C. 17/1545Z
D. 15.0N 74.50W
E. 17/1615Z TO 18/2015Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: BEGIN 12-HRLY FIXES
AT 18/1200Z IF SYSTEM DEVELOPS.
3. REMARK: INVEST FOR SUSPECT AREA SOUTHEAST OF
BERMUDA FOR 16/1800Z CANCELED BY NHC AT 16/1300Z.


II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
TMB
I think the above is a case of lazy editing of the prior day's POD, but given that the only scheduled flight for today at 16/1800Z was to investigate the Carribean disturbance, and today's flight was cancelled, it would seem most likely that there will be no recon into this. But we shall see shortly.

Latest ASCAT shows this is still a wave without a closed circulation:

[ozonepete]

I think it's at least plausible that some kind of LLC is trying to form.

LOOP: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... map=latlon

Overall flow is still east to west but low level motion is starting into the area of storms.

Yeah, Mark, I see it too. Looks like it waited for NHC to cancel the RECON before ramping up.

[dolebot_Broward_NW]

Interesting that the curved cloud out ahead of the area of main convection has persisted as long as it has. Something must have shut off her fuel in a hurry to have the storms collapse and poof like that. I'm noting some action along that boundary. Would this serve to stabilize the atmosphere? Here when t-storms collapse like that often new ones form along that same boundary, but not sure it works in the deep tropics.

That's not a thunderstorm outflow boundary like we usually see. The usual ones are low-level and produced by a collapse downward of dry air which then rushes out in an arc which is a forward rushing boundary that acts like a micro or macro front that can initiate new storms, as you said.
This is a high level arc cloud that is mostly cirrus. It is a gravity wave that was left over from the high level cirrus outflow, so it will not create any new weather of its own and should dissipate soon.

Ah thank you, I knew it couldn't be the same, it was WAAAAY too big!

[ozonepete]

You're welcome. I don't know if you ever use the RBG satellite images and loops, but they are really great during daylight hours for seeing more of the storm and cloud structures. The yellow represents low clouds, the white for mid to upper level clouds and bluish colors show the highest clouds, such as cirrus. Look at this loop and you'll see clearly how those are high clouds:

http://www.ssd.noaa.gov/goes/flt/t1/flash-rgb.html

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT TUE AUG 16 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM GERT...LOCATED ABOUT 410 MILES NORTHEAST OF BERMUDA.

A LARGE TROPICAL WAVE OVER THE EASTERN CARIBBEAN SEA IS PRODUCING
SCATTERED SHOWERS AND THUNDERSTORMS FROM HISPANIOLA EASTWARD ACROSS
PUERTO RICO...THE VIRGIN ISLANDS...AND THE LEEWARD ISLANDS. THERE
ARE NO SIGNS OF A SURFACE CIRCULATION AT THIS TIME. HOWEVER...SLOW
DEVELOPMENT OF THIS WAVE IS POSSIBLE DURING THE NEXT FEW DAYS AS IT
MOVES WESTWARD AT NEAR 20 MPH. THIS SYSTEM HAS A LOW CHANCE...20
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BEVEN