East Coast development soon? Floater named "INVEST"

[KWT]

Since there is a thread on the SW Caribbean system I thought it may be worthy to also make a thread for a system the models are developing off the east coast of the US.

At first it would be cold cored, that I have no doubts about. However much depends on its track, if it were to scoot off into the Atlantic I doubt it'd have enough time to change even to subtropical, but if the 0z ECM solution of it heading back west towards the Gulf Stream is correct, then a system perhaps like Andrea in 07 can't be ruled out IMO...

[cycloneye]

Here is the ECMWF with the agressive run developing this.

[KWT]

I'd imagine it wouldn't be a pure tropical development but it isn't impossible to get a fairly potent system in that part of the basin if it can get over the GS....hurricane Able which developed in mid May is the best example of that...

[HURAKAN]

Everything is coming together:

[pepeavilenho]

Do yo really think it could become tropical?

I'm not really sure about that, because JET is near.

I see 70% non-tropical...but we''ll see.

[KWT]

Well I'm not sure it'd be 'tropical' so to speak, but if it moves as the ECM suggests, then its going to get over the GS and as we've seen that can be a place where real tropical development can occur even in May. I think a subtropical system is possible down the line.

[HURAKAN]

It's possible it can be subtropical and even tropical. Ana in 2003 formed in the same general area in April and achieved tropical storm status

[KWT]

Exactly, if it can hang about long enough then things could become interesting thats for sure IMO...

I'd certainly think the ECM solution this morning would lead to at least subtropical development.

[hurricanetrack]

Well, there's this:

http://moe.met.fsu.edu/cyclonephase/gfs ... 6/119.html

Tropical at first then not so much........

[cycloneye]

12z CMC

CMC is strong with it.

[KWT]

Well, there's this:

http://moe.met.fsu.edu/cyclonephase/gfs ... 6/119.html

Tropical at first then not so much........

That is assuming the track is what the GFS expects, the 0z ECM had a rather different track which would make it far more likely to gain tropical features...I promise it won't be tropical at first though, not with the way it will develop...

[cycloneye]

12z ECMWF

The 12z run of the EURO has the Western Atlantic system more stronger than in past runs.

[KWT]

Yep once again the ECM 12z run would probably lead to a sub/tropical system and probably a decent one at that...

I'd think a system perhaps close to STS Andrea is possible with this set-up...could have 2 systems before the end of May at this rate, though I think this has more of a chance of coming off IMO...

[cycloneye]

From the Melbourne AFD.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
325 PM EDT WED MAY 19 2010

WILL ALSO BE TRACKING TWO FEATURES OF INTEREST THROUGH THIS WEEKEND
...ALONG WITH HOW THE SUBSEQUENT MODEL RUNS CONTINUE TO HANDLE THESE
FEATURES. THE FIRST IS THE AFOREMENTIONED WRN ATLC SHORT WAVE TROUGH
THAT WILL SPIN UP A SFC LOW SOMEWHERE BTWN 25-30N AND 70-75W. THE
SECOND AND MORE IMPACTING FEATURE (EVENTUALLY) WILL BE THE NRN
STREAM SHORT WAVE TROUGH WHICH MOVES ENEWD THROUGH THE MIDWEST AND
GRT LKS RGNS FRI/ SAT...THEN MAKES AN ABRUPT RIGHT HAND TURN ON
SUN...DROPPING EITHER SHARPLY SWD ALONG THE MID ATLC/SERN SEABOARD
(GFS SOLN) OR SSE INTO THE WRN ATLC WHERE IT PHASES WITH THE
TROUGH/LOW ALREADY THERE AND BECOMES VERTICALLY STACKED (ECM SOLN).
GIVEN THE PRONOUNCED UPSTREAM AMPLIFICATION...SIGNIFICANT HGT FALLS
APPEAR LKLY ALONG OR JUST OFFSHORE THE EAST COAST. EXACTLY WHERE
THIS OCCURS WILL DETERMINE THE EXTENT OF INTERACTION BTWN THE TWO
SYS...AND HENCE HAVE HUGE FCST RAMIFICATIONS LCLY...ESPEC FROM MON
ONWARD.

MON-WED...FCST BCMS UNCERTAIN GIVEN THE DISPARITY IN THE GFS/ECM
SOLNS. IT IS IMPORTANT TO NOTE THAT THE LATEST GFS IS STRONGER AND
MORE CUTOFF AT H50 THAN PREV RUNS...AND THUS HAS TRENDED TWD THE
ECM. BRAND NEW 12Z ECM HOT OFF THE PRESSES IS ALMOST IDENTICAL TO
IT`S 00Z SOLN AT BOTH THE SFC AND H50...ALBEIT JUST A BIT FATHER
NORTH WITH WHERE THE STACKED LOW MOVES INTO THE SERN CONUS (CLOSER
TO THE FL/GA BORDER RATHER THAN INVOF SGJ-DAB). WHAT SEEMS MORE
CERTAIN IS THAT THE UPPER SYSTEM WILL BE FAIRLY STOUT AND WILL
RETROGRADE SWWD UNDERNEATH THE STRONG UPPER HIGH TO ITS NORTH...
EVENTUALLY WINDING UP CLOSE ENOUGH TO CTRL/NORTH FL TO PRODUCE
UNSETTLED WX BY TUE/WED. SHOULD CONTINUE TO SEE AN ONSHORE FLOW
REGIME...SOMETHING BTWN ENE AND NE...WITH SUFFICIENT MOISTURE TO
PRODUCE AT LEAST SCT POPS...PSBLY HIGHER

[pepeavilenho]

JET independence:

+120 horas

+126 horas

+132

+138

+144


I trust it won't be non-tropical at the beginning....let's see

[AJC3]

I trust it won't be non-tropical at the beginning....let's see

Quite the contrary...it will be non-tropical at the start. I don't think anyone here has said that this won't be a B/I (baroclinically initiated) low given the pressure falls will be dynamically forced via upper level jet divergence. It will also be cold cored aloft given there will be an existing mid level trough that will give way to an even stronger mid to upper level cutoff low dropping southward over the western Atlantic. Without a cold core mid level trough/low aloft, SST's won't be warm enough to support central convection. At best...IMNSHO...this low may transition to a hybrid.

[cycloneye]

Subtropical.

[pepeavilenho]

I trust it won't be non-tropical at the beginning....let's see

Quite the contrary...it will be non-tropical at the start. I don't think anyone here has said that this won't be a B/I (baroclinically initiated) low given the pressure falls will be dynamically forced via upper level jet divergence. It will also be cold cored aloft given there will be an existing mid level trough that will give way to an even stronger mid to upper level cutoff low dropping southward over the western Atlantic. Without a cold core mid level trough/low aloft, SST's won't be warm enough to support central convection. At best...IMNSHO...this low may transition to a hybrid.

No, my friend, firstly it will have warm core, then the extratropical transition..

Take a look.

http://moe.met.fsu.edu/cyclonephase/gfs ... 2/128.html

This is not a low bornt from the JET with cold core, It borns near Hispaniola island, SE of Bahamas.

[AJC3]

No, my friend, firstly it will have warm core, then the extratropical transition..

Take a look.

http://moe.met.fsu.edu/cyclonephase/gfs ... 2/128.html

This is not a low bornt from the JET with cold core, It borns near Hispaniola island, SE of Bahamas.

100% wrong, my friend. I had a look at MUCH more, higher resolution data at work today compared to the coarse resolution images that you posted earlier. A phase diagram showing a forecast of at best a marginal, shallow warm core is unconvincing given the synoptic setup. The low north of Hispanola will form due to jet forced ascent, which will cause the pressure falls. Read the AFD out of Melbourne...I wrote it.

[pepeavilenho]

100% wrong, my friend. I had a look at MUCH more, higher resolution data at work today compared to the coarse resolution images that you posted earlier. A phase diagram showing a forecast of at best a marginal, shallow warm core is unconvincing given the synoptic setup. The low north of Hispanola will form due to jet forced ascent, which will cause the pressure falls. Read the AFD out of Melbourne...I wrote it.

Right, sorry

But in the charts there's no relation between the low and the JET at +120 hours.

Probably you're right, but if there's a relation between JET and Low, there's no chance that it is tropical, isn't?