Tropical Development at Bahamas / GOM in comming days?

[DESTRUCTION5]

Umm..I don't think we could have more consensus that that can we Folks?

Good catch Vortex....Looks more Probable that possible IMO...

[frederic79]

Does anyone know offhand what typical shear tendencies in the Gulf are 2-3 days after the passage of an early fall cool front. I realize other factors play into this, but I'm strictly asking if there is a typical, historical synoptic response to the passage of a cool front and what it does to upper level winds 2-3 days after it stalls out. We know this will happen late Friday/early Saturday. This is 2-3 days before some models forecast development in the NW Carribean.

[frederic79]

Correction: Carribean = Caribbean.

[Frank2]

Yipes - the earlier FSU model was for October 25, 2006 - well, at least I had the day correct...

LOL

[Tampa Bay Hurricane]

DISCLAIMER: The Following is a Reaction to Low Shear and is NOT OFFICIAL!!!!!!

HOLY CRAP check out the almost zero shear all acorss
the bahamas and Haiti west!!! This area is almost perfect for
some Great Tropical Action.

As soon as the wave moves into this area it will create
a tight pressure gradient with a building ridge to the north
and could likely develop as to what the models say.

And I mean this will LIKELY Develop. Karen/Ingrid's
conditions cannot even be compared with this-
I mean zero shear- that is some wild potential people!!!!!
http://cimss.ssec.wisc.edu/tropic/real- ... g8shr.html

This tropical wave should explode once it hits this area and
I expect rapid development of something tropical here. Shear is what
prevented other storms from intensifying but in this case, holy smokes,
shear is almost extinct!

In fact you can ALREADY began to see some Serious
Convection Flaring up along the tropical wave,
and I think it is gonna flare up much more
I mean look at that lack of shear.
Also the heat content is high, but the big news
here is that this is the only part of the basin with
a big area of near zero shear!
http://www.goes.noaa.gov/browsat.html

Infrared Picture:



And if you still have ANY doubts that this will develop just look
at lorenzo in the only other part of the basin with near 0 shear-
TD to almost hurricane in a few hours.

THAT is the type of potential IF the shear stays near 0-10 knots
over the bahamas.
Not saying that there will be something that intense- but look
at my POINT- IN 2007 WHEN SHEAR DECREASES STORMS EXPLODE!

[cpdaman]

well the rotation in the convection in the area of the extreme se bahamas (a la 72W) and nw hispanola has caught my eye, it seems a bit AHEAD of schedule for a sunday event, BUT we shall see.

http://www.ssd.noaa.gov/goes/east/watl/loop-vis.html block first two frames and speed up loop (shows rotation over se bahamas better)


btw shear does not mean we won't have a decent system out there it just may be nor'easter type or subtropical, but i am not sold on shear yet either, especially if the scheduled development of this system is to be sped up

[Steve]

>>Does anyone know offhand what typical shear tendencies in the Gulf are 2-3 days after the passage of an early fall cool front.

You have to go by the repetition in the current pattern. Admittedly, I haven't even looked at the upper patterns, but assuming this isn't some longwave trough and is just a front ahead of a cool high settling in from the north/northeast as they have been doing since early August, it would be front washes out with a piece streching back SW. (Last one looked like a piece of ridge split but I'm sure it had to be a trough split because you don't hear about high splits that often.) High settles in and moves eastward as SW Atlantic ridging moves back in from the SE. Flow across the gulf goes from interrupted out of the north then east winds at the surface and then southeast winds until SW winds come in ahead of the next system. The progression should become faster as the season moves on with a possible temporary respit for Indian Summer if the flow eases back to zonal above 40N often resulting in the collapse of steering currents (see Juan 1985).

JMO

Steve

[Wx_Warrior]

New 0z EURO has nothing for GOM....

[frederic79]

However the euro is depicting an intense storm approaching south Florida from the east in 10 days. Way to far out to put much stock in this.

[Steve H.]

Well, here's more reading for indigestion, I mean ingestion. This is the longest writeup I've seen from Camp Springs, MD on a potential low pressure

ALL MODELS LEAVE A WEAKNESS BETWEEN THE BASE OF AN EXITING NRN
STREAM TROF AND SUBTROPICAL WEAKNESS BETWEEN GULF MEX AND MS
VALLEY RIDGING AND RIDGING EWD IN THE ATLC.
CANADIAN MODEL EVER AGGRESIVE WITH TROPICAL CYCLOGENESIS CONTS TO
DAILY GENERATE A TROPICAL CYCLONE IN THIS AREA. MOST OF THE TIME
WAY OVERDONE BUT THE MODEL HINTS AT FAVORABLE CONDS FOR
CYCLOGENESIS TROPICAL OR NOT. ALL OTHER MODELS INCLUDING GFS AND
ECMWF ENSEMBLES INDICATE LOW PRESSURE IN THIS AREA FROM DAYS 4 TO
7. EXCLUDING THE DAILY OVERDONE CANADIAN WITH ITS HURRICANE THERE
REMAINS TWO CAMPS..GFS AND NOGAPS TAKING A WEAK LOW WWD THRU THE
FLORIDA STRAITS INTO THE GULF MEXICO AND THE ECMWF/GFS ENS MEAN
AND UKMET WHICH DEVELOP MORE LOW PRESSURE IN THE BAHAMAS. THE
ECMWF/UKMET MID LEVELS ARE PREFERRED WITH THE UKMET SFC DEPICTION
AT 144 HRS INDICATING A SIG LOW IN THE NRN BAHAMAS CAPPED BY HIGH
PRESSURE NWD OFF THE NEW ENG COAST SETTING THE STAGE FOR AN
INVERTED COASTAL TROF NWD FROM OFF THE MID ATLC COAST SWD TO THE
BAHAMAS LOW. MID LEVEL FLOW EXTRAPOLATION OF THE ECMWF AND UKMET
WOULD DRIFT ANY SFC LOW IN THIS AREA NWD. DGEX ALSO HAS A VERY SIG
LOW MOVING NWD TO ALONG THE MID ATLC COAST SIMILAR AND FASTER THAN
EXTRAPOLATION OF 00Z UKMET. ECMWF/UKMET/DGEX AND YTDAS 12Z CMC
DEVELOP THE SOUTHEAST COAST/ BAHAMAS LOW ON A STATIONARY FRONT AND
RETROGRADE IT WWD TOWARDS THE COAST.

HPC UPDATED PROGS HAVE LOW PRESSURE SLOWLY MOVING NWD OFF THE
SOUTHEAST COAST DAYS 6 AND 7 WED/THU WITH A CONTD INVERTED SFC
TROF OFFSHORE. PHASE DIAGRAMMING OF THE UKMET INDICATES A HYBRID
SYSTEM AS THIS FORMS OFF A RETROGRADING FRONTAL WAVE AND COMBINES
WITH A POSSIBLE LOWER LATITUDE TROPICAL IMPULSE. TROPICAL ENSEMBLE
MEANS INDICATE THAT THIS AREA OFF THE SOUTHEAST COAST WOULD
POTENTIALLY HAVE WEAK SHEAR DAYS 5 AND 6 TUES/WED. INCREASING
CONFIDENCE OF LOW PRESSURE FORMATION IN THIS AREA..LOW CONFIDENCE
IN POSITION.

[Tampa Bay Hurricane]

that write up emphasizes the decreasing shear...

[cpdaman]

well that would be a nice set up for waves in florida i do beleive. still a long way off i guess. sounds like sub tropical or hybrid as well

[PhillyWX]

I have access to 12 hour EURO and it has brought an area of low pressure and moisture up the coast for the last 2 runs. The origination point is the Bahamas and then it brings it slowly up to around Jacksonville by hour 156. This low lingers over Florida after that; however, moisture streams up the coast. This could be a situation similar to 98L where the main moisture streams up the coast and a low effectively sat back stationary and lost its moisture source.

For those who care, this is not Karen. Karen is situated north of Hispaniola by H180 on today's 12z.

[americanrebel]

The local Mets in Lafayette, La., said we need to be watching the GOM mid to late next week. Why should we?

[Tampa Bay Hurricane]

Convection now flaring up along this
tropical wave in an area of almost zero shear-
THIS is the area that eventually goes into the gulf:
THIS is what the models Develop IN THE GULF EVENTUALLY:

[Tampa Bay Hurricane]

What is being developed in the gulf is the area near the
bahamas- that tropical wave is what is moving towards
and will develop possibly in the Gulf. For more
information go to that thread.

[Stormcenter]

The local Mets in Lafayette, La., said we need to be watching the GOM mid to late next week. Why should we?

I honestly don't know except that the GFS is developing another phantom storm. From what I'm reading it may start out or remain a hybrid system if it does develops. I have my doubts but the GFS did correctly predict TD10 so it may be on to something. I am waiting until it actually forms before I become concerned. IMO

[Stormcenter]

Well, here's more reading for indigestion, I mean ingestion. This is the longest writeup I've seen from Camp Springs, MD on a potential low pressure

ALL MODELS LEAVE A WEAKNESS BETWEEN THE BASE OF AN EXITING NRN
STREAM TROF AND SUBTROPICAL WEAKNESS BETWEEN GULF MEX AND MS
VALLEY RIDGING AND RIDGING EWD IN THE ATLC.
CANADIAN MODEL EVER AGGRESIVE WITH TROPICAL CYCLOGENESIS CONTS TO
DAILY GENERATE A TROPICAL CYCLONE IN THIS AREA. MOST OF THE TIME
WAY OVERDONE BUT THE MODEL HINTS AT FAVORABLE CONDS FOR
CYCLOGENESIS TROPICAL OR NOT. ALL OTHER MODELS INCLUDING GFS AND
ECMWF ENSEMBLES INDICATE LOW PRESSURE IN THIS AREA FROM DAYS 4 TO
7. EXCLUDING THE DAILY OVERDONE CANADIAN WITH ITS HURRICANE THERE
REMAINS TWO CAMPS..GFS AND NOGAPS TAKING A WEAK LOW WWD THRU THE
FLORIDA STRAITS INTO THE GULF MEXICO AND THE ECMWF/GFS ENS MEAN
AND UKMET WHICH DEVELOP MORE LOW PRESSURE IN THE BAHAMAS. THE
ECMWF/UKMET MID LEVELS ARE PREFERRED WITH THE UKMET SFC DEPICTION
AT 144 HRS INDICATING A SIG LOW IN THE NRN BAHAMAS CAPPED BY HIGH
PRESSURE NWD OFF THE NEW ENG COAST SETTING THE STAGE FOR AN
INVERTED COASTAL TROF NWD FROM OFF THE MID ATLC COAST SWD TO THE
BAHAMAS LOW. MID LEVEL FLOW EXTRAPOLATION OF THE ECMWF AND UKMET
WOULD DRIFT ANY SFC LOW IN THIS AREA NWD. DGEX ALSO HAS A VERY SIG
LOW MOVING NWD TO ALONG THE MID ATLC COAST SIMILAR AND FASTER THAN
EXTRAPOLATION OF 00Z UKMET. ECMWF/UKMET/DGEX AND YTDAS 12Z CMC
DEVELOP THE SOUTHEAST COAST/ BAHAMAS LOW ON A STATIONARY FRONT AND
RETROGRADE IT WWD TOWARDS THE COAST.

HPC UPDATED PROGS HAVE LOW PRESSURE SLOWLY MOVING NWD OFF THE
SOUTHEAST COAST DAYS 6 AND 7 WED/THU WITH A CONTD INVERTED SFC
TROF OFFSHORE. PHASE DIAGRAMMING OF THE UKMET INDICATES A HYBRID
SYSTEM AS THIS FORMS OFF A RETROGRADING FRONTAL WAVE AND COMBINES
WITH A POSSIBLE LOWER LATITUDE TROPICAL IMPULSE. TROPICAL ENSEMBLE
MEANS INDICATE THAT THIS AREA OFF THE SOUTHEAST COAST WOULD
POTENTIALLY HAVE WEAK SHEAR DAYS 5 AND 6 TUES/WED. INCREASING
CONFIDENCE OF LOW PRESSURE FORMATION IN THIS AREA..LOW CONFIDENCE
IN POSITION.

Huh? I couldn't resist. I'm sorry but all that for what we have now which is nothing.
Hey I guess they have to write about something. The good news is we have a nice front coming through and that should keep anything away from my area for at least the next 5 days. IMO

[cpdaman]

from miami discussion and jacksonville discussion tonite

there are two different but BEARISH outlooks for a low to develop

miami disc says a front will sweep thru S. FL and a low will form in n. bahamas tuesday nite and move rapidly NE

jacksonville says a ULL will form in either E. gulf or E of florida and retrograde west w/ a weakening area of low pressure in the mix

looks like all eyes will watch to see the matchup between "large and maybe in charge Karen" vs. " the hurricane killa ;"shearzilla" which will be decided b4 sunday's football kickoff. enjoy

[BigA]

There certainly is farily deep convection flaring up in the eastern Bahamas. Worth watching for persistance.