Caribbean Tropical Development 2011, Until Invest Formation ONLY - Waves and LPs Options

[Phased Vort]

2011 Caribbean Development Discussion Thread

The Map below shows the geographical area allowed for discussion in this thread.




This thread is the 2011 version of the former 2010 Caribbean Discussion thread.
In here we will discussion and post about possible development of tropical systems prior to their classification to INVEST status by the NHC.

Origin/Reason for development:
African Waves aka Eastern Waves
Low Pressure areas

***Let the discussion flow well, unhindered by the violation of the forum rules.***
Thanks!

[The Day After To...]

Hey PV! Nice to see you again.

The long range GFS has been showing something in the Carribean. Here is hours 348, 360, 372, and 384.

Attached thumbnail(s)

 

[Phased Vort]

Long long range GFS, on its 12z and 18z runs of today, have shown possible tropical development in the eastern to central Caribbean by mid May.


Given itīs showing the possibility in the Caribbean, I would say itīs more possible, as its the first place to look for development so early in the season.


So yea, the GFS has started its usually well done job of sniffing out possible tropical activity far out into the future.

[Phased Vort]

Hey PV! Nice to see you again.

The long range GFS has been showing something in the Carribean. Here is hours 348, 360, 372, and 384.

Hello!

Thanks!

Yep. I saw it.

[NorEaster07]

Nice call Carlos! Nice to see you again.

Gulf and Carribean current water temps showing 80+


GFS12z hrs 204, 228, 240, 252

At 204 it clearly is showing something juicy in Gulf. And then a MillerA type setup.




This post has been edited by NorEaster07: May 12 2011, 05:06 PM

[east coast storm]

Nice call Carlos! Nice to see you again.

Gulf and Carribean current water temps showing 80+


GFS12z hrs 204, 228, 240, 252

At 204 it clearly is showing something juicy in Gulf. And then a MillerA type setup.

As you know the gfs shows a low coming up the eastern seaboard from the Carolinas
midweek nextweek. Then we turn our attention to the sub or semitropical
low in the gulf coming up the EC next weekend. Could be really interesting.

[weather-major94]

As you know the gfs shows a low coming up the eastern seaboard from the Carolinas
midweek nextweek. Then we turn our attention to the sub or semitropical
low in the gulf coming up the EC next weekend. Could be really interesting.

hmm. well, okc could really use some rain. perhaps we could get some.

[Superstorm93]

The 18z GFS is pretty much a carbon copy of the "Alma-Arthur Basin Switch" back in 2008.

Of course it's 15 days out though.

Purely trivial.

[Phased Vort]

As we head into late May and early June, the Caribbean indeed needs to be payed attention to, as overall pressure over the Caribbean naturally fall over the warm Caribbean SSTs. And in case a more permanent high pressure ridge develops over the Caribbean forcing a constant east to west flow, as an extension of a maturing CAR over the northern parts of the Atlantic ocean, a couple of invests may make themselves known and have a shot at actual depression status.

[jdrenken]

Throwing into the mix...

A reminder that each major coastal that hit MidAtl/NE during the winter started as a potent storm in the Gulf.

[weather-major94]

As we head into late May and early June, the Caribbean indeed needs to be payed attention to, as overall pressure over the Caribbean naturally fall over the warm Caribbean SSTs. And in case a more permanent high pressure ridge develops over the Caribbean forcing a constant east to west flow, as an extension of a maturing CAR over the northern parts of the Atlantic ocean, a couple of invests may make themselves known and have a shot at actual depression status.

it seems likely, is there an updated SST map out there for the caribbean? (a link is fine.)

[east coast storm]

Nice call Carlos! Nice to see you again.

Gulf and Carribean current water temps showing 80+


GFS12z hrs 204, 228, 240, 252

At 204 it clearly is showing something juicy in Gulf. And then a MillerA type setup.

As you know todays friday the 13th 12Z GFS does not show that low in the gulf anymore.
Weather is always changing. Maybe on the next few runs that low might come
back.

[weather-major94]

As you know todays friday the 13th 12Z GFS does not show that low in the gulf anymore.
Weather is always changing. Maybe on the next few runs that low might come
back.

ah, meteorolgy, the guessing game. very fun if you ask me. i think the low pops up in 2 runs, these models arent perfect.

This post has been edited by weather-major94: May 13 2011, 11:00 AM

[MAC292OH10]

as shear starts to wane and an anti cyclone builds into the carribbean region , there will be the possibility of a weak disturbance to emerge from the Caribbean late in the month into june...whether it just makes lemon drop, invest or possible TD is anybody's guess, but the potential should be there...

[weather-major94]

as shear starts to wane and an anti cyclone builds into the carribbean region , there will be the possibility of a weak disturbance to emerge from the Caribbean late in the month into june...whether it just makes lemon drop, invest or possible TD is anybody's guess, but the potential should be there...

we do currently have a wave off the NE coast of brazil, it is getting late in the month.
here is the discussion:
...TROPICAL WAVES...

A TROPICAL WAVE IS ANALYZED OFF THE COASTAL WATERS OF NE BRAZIL
FROM 10N44W TO 1N48W. THE WAVE IS DRIFTING WEST AT ABOUT 5-8 KT.
THIS WAVE SHOWS UP WELL AS A BROAD MOISTURE SURGE ON TOTAL
PRECIPITABLE WATER IMAGERY. THE MOST RECENT WINDSAT PASS REVEALS
VERY LITTLE CYCLONIC CURVATURE IN THE FAR SOUTHERN EXTENSION OF
THE AXIS...AND ENE WINDS UP TO 20 KT SURROUNDING THE REMAINING
EXTENSION OF THE WAVE AXIS. THIS WAVE IS GENERATING SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION S OF 7N BETWEEN 43W-53W
AFFECTING THE COASTAL WATERS OF NE BRAZIL AND FRENCH GUIANA.

...ITCZ...

THE ITCZ AXIS IS ANALYZED FROM THE COAST OF SIERRA LEONE NEAR
7N12W S-WESTWARD ALONG 4N20W 2N30W. THEN...IT RESUMES OFF THE
COAST OF BRAZIL NEAR 3S38W AND CONTINUES NW INTERSECTING THE
TROPICAL WAVE NEAR 2N47W. SCATTERED MODERATE TO ISOLATED STRONG
CONVECTION IS WITHIN 120 NM ON EITHER SIDE OF THE ITCZ E OF 30W.
AN EMBEDDED SURFACE TROUGH IS ANALYZED WITHIN THIS AREA OF
CONVECTION EXTENDING FROM 6N24W TO 2N26W.

Source: http://www.nhc.noaa.gov/text/refresh/MIATW...ml/151758.shtml

This post has been edited by weather-major94: May 16 2011, 12:53 PM

[Superstorm93]

Looking forward to a season where the MJO is more behaved than last year.

[weather-major94]

Looking forward to a season where the MJO is more behaved than last year.

that would be helpful.. XD

By the way, your signature is pretty funny.

This post has been edited by weather-major94: May 16 2011, 01:14 PM

[weather-major94]

that would be helpful.. XD

By the way, your signature is pretty funny.

allright, time to ask for a professional opinion, does anyone sense a chance of development, or is the environment north of it still too harsh?

[Removed_Member_OHweather2_*]

Well, the environment looks to favor potential early season development over the next couple of weeks over either the southern Caribbean of eastern Pacific, if we can get an actual disturbance in the area.

Right now there is a surface high pressure over the southern Caribbean, and any real ITCZ is too far south for development in the Caribbean at this time:


Note the broad anti-cyclonic flow over the Caribbean.

Aloft, the subtropical jet is running through the majority of the Caribbean. However, the jet is running north of the southern Caribbean, leaving an area with some upper level divergence and lower shear over the southern Caribbean, which is moderatly favorable for development:



This is expected to continue for easily one, if not two or more weeks. Note the ECM forecast valid a week from this morning:



The GFS upper level forecast valid June 2nd shows a similar jet configuration in place over the Caribbean, with the subtropical jet if anything slightly farther north and a larger upper level anti-cyclone providing a favorable low shear/good divergence environment for development over the southern Caribbean or eastern Pacific in two weeks:



Given this favorable pattern over an area of waters easily warm enough for tropical development, the question becomes will a system move into the area and take advantage of the favorable early season environment?

Currently, there is a large area of good MJO induced lift over the eastern Pacific into the western Atlantic. However, there is an MJO pulse moving over Africa into the Indian Ocean which will likely be the main player for potential development down the road:



As this pulse begins moving east this upper level lift should decrease some over the area of interest. However, many models attempt to show the pulse stalling some and weakening over the western Pacific within 10-14 days, which would at least be neutral for development over the area of interest/eastern Pacific by the beginning of June:

Note the GEFS ORL forecast above.

Before this time, the ECM does show something slightly interesting a week out, with a weak piece of vorticity splitting off what is likely the ITCZ and spinning up a weak low in the aformentioned favorable environment for development, although the model does weaken it rather quickly:



So essentially, a marginally favorable environment for development quite possibly may exist over the southern Caribbean/eastern Pacific for the forseeable future. Whether or not we see a system to develop is in the air, although as the ITCZ slowly drifts north and becomes more organized as we move into June chances will slowly increase. These systems tend to favor the eastern Pacific side of central America this early in the season, though that's not to say we won't see something trackable in teh Caribbean over the next 2-4 weeks.

[CanadianKeegan]

GFS has been hinting at something forming in two weeks... Probably picking up on the MJO being strong by then.