Global Model Runs for W.Caribbean Early Season Development

[cycloneye]

00z GFS Loop Here is the 00z loop.No Hurricane here.Storm weakens in GOM and splits.

[Eyewall]

There is no way I believe that will happen.

[gatorcane]

Here is the 72 hour TAFB. Notice the low in the EPAC with the arrow pointing right. That low may be what ends up being the "Western Caribbean low."

[Opal storm]

There is no way I believe that will happen.

But you'll believe it if it shows a hurricane?

It's not even June, things aren't quite ripe enough yet. Enjoy these quiet times, the big ones will be here too soon enough.

[Eyewall]

I think in the long term future any where form the central gulf coast to florida will be on the look out. And I would not be surprised if the turns out to be from Texas to Florida. I have a feeling this will be one of those stormes that will not follow what histrory says it should go this time of year.

[gatorcane]

If you take a look at the IR loop, you will see the 1007 MB low the TAFB surface forecast is predicting will push ENE. There is a noticeable spin around 10N ~95W.

http://www.ssd.noaa.gov/goes/east/watl/loop-avn.html

Here is a snippet from the discussion:

GLOBAL MODELS ARE FORECASTING A BROAD AREA OF LOW PRESSURE TO
DEVELOP NEAR 10N90W OVER THE NEXT SEVERAL DAYS

[NDG]

00z CMC:

[Eyewall]

What type of steering currents are set up to move the low east like that. Because normally a developing storm of the Mexico coast moves west out to sea.

[Eyewall]

You can see that there is a developing broad area of low pressure there.

[gatorcane]

What type of steering currents are set up to move the low east like that. Because normally a developing storm of the Mexico coast moves west out to sea.

From the NHC discussion. This windflow is going to push any surface lows to the East or East Northeast. This type of setup is most likely to happen in May for the EPAC and has brought other disturbances over to the Caribbean, although its not a likely scenario for creating Western Caribbean tropical systems.

A BROAD AREA OF SW TO W WINDS TO 20 KT CONTINUE OVER THE WATERS
FROM 3N TO 08N BETWEEN 88W AND 110W.

[rainydaze]

yeah it seems ENE moving storms coming from the carribean are mostly in the late season. Usually early season storms head over towards Texas.

[Meso]

00z NOGAPS : 132 Hours


00z CMC : 144 Hours

The animation is interesting : http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation


The 00z EURO doesn't show much

Extended range CMC (Whoa Nelly)




Increasing convection in the EPAC

[KWT]

I think its safe to say the CMC is rather overdoing it probably. However the models are comin g into better agreement on the track of any tropical cyclone within 168hrs. After that on the 0z run the system takes the strangest path I've seen a June system take and goes rather against what you tend to see at this time of year, not impossible but I wouldn't guess very likely.

ECM doesn't show anything forming on this run however so still not total agreement yet.

[NDG]

ECM has been very inconsistant, however it still shows lower pressures in the NW Caribbean on its latest run.

[Thunder44]

At 240hrs, the 0z GGEM has it down to 962mb, just off the Florida SE coast:





I've noticed that the GGEM, GFS, and NOGAPS have been more bullish about development of this storm in the NW Carribean and the Gulf than Euro and Ukmet which keep more development in the EPAC.

[Meso]

06z GFS 48 Hours
A 1007mb low in the E.Pac

06z GFS 66 Hours
Already at 66 hours there are 2 1006mb lows in both the E.Pac and the Caribbean

06z GFS 120 Hours
Still 1006 mb low,but the majority of the energy enters the Caribbean

06z GFS 162 Hours
A 1001mb low heading across the Yucatan peninsula

06z GFS 216 Hours
997mb Storm hitting Florida

[NDG]

NWS MLB AFD

AREA FORECAST DISCUSSION...CORRECTED TO REMOVE SCA FFROM W/W/A
NATIONAL WEATHER SERVICE MELBOURNE FL
410 AM EDT MON MAY 26 2008

.DISCUSSION...


TUE-THU...STOUT DEEP LYR RIDGE WITH AXIS NORTH OF FLORIDA WILL
WEAKEN AT ALL LEVELS DURING THE SHORT RANGE. W/R/T SENSIBLE WX
...CWA WILL BE LOOKING AT CONTINUED WEAKENING OF ONSHORE FLOW
WITH GRADUAL INCREASE IN MEAN LYR MOISTURE...ENOUGH TO WHERE
RH VALUES AND T/TD WILL RISE CLOSER TO LATE MAY/EARLY JUNE NORMS
...BUT NOT QUITE ENOUGH TO PRODUCE PRECIP AS DEEP MOISTURE ASCD
WITH POTENTIAL WRN CARIBBEAN DISTURBANCE IS PROGGED BY ALL MODELS
TO STAY SOUTH OF THE STATE...FOR THE TIME BEING.

FRI-MON...AM GENERALLY LOATH TO DISCUSS POTENTIAL T.C. DEVELOPMENT
DURING THE `PRE-SEASON`...PARTICULARLY IN THE XTD RANGE. HOWEVER...
MANY OF THE GLBL MODELS HAVE BEEN SUGGESTING THE POSSIBILITY FOR THE
BETTER PART OF A WEEK...AND CONTINUE TO HOLD ONTO THIS FEATURE...
WHOSE POTENTIAL GENESIS HAS NOW COME INTO THE DAY 3-5 RANGE. ALSO...
POTENTIAL LOW PRES FORMATION TO OUR SW COULD AT THE VERY LEAST HAVE
SIGNIF IMPACT ON POP FCST (GIVEN THE ONGOING DEARTH OF MAY RAINFALL).
HENCE...IT BEHOOVES ME TO GIVE THIS FEATURE SOME MENTION.

BY FRI 12Z...ALL GLBL MODELS SHOW A GENERAL BROAD LOWERING OF SLP
ON BOTH THE EPAC AND CARIB SIDE OF CTRL AMERICA. THEN THRU SUN/MON
...THE GFS/NGP/GGEM CONTINUE THEIR TREND IN AGGRESSIVE SPINUP OF A
T.C...EVENTUALLY BRINGING A SYSTEM NWD TO NEAR/NORTH OF THE YUCATAN
WITH SIGNIFICANT INCREASE IN DEEP LYR MOISTURE...ESPECIALLY OVER
SOUTH FL. ON THE OTHER END OF THE SPECTURM ARE THE UKM/ECM...WHICH
ARE GENERALLY SUPPRESSED MUCH FARTHER SOUTHWARD...AND AS A RESULT
NOT NEARLY AS AGGRESSIVE WITH NWD MOISTURE RETURN. SHOULD BE OF
SOME INTEREST TO WATCH HOW THIS SYSTEM PROGRESSES...IF AT ALL.

FOR THIS FCST...HAVE CONTINUED THE CONSERVATIVE TREND IN SHOWING A
GRADUAL INCREASE IN MOISTURE FROM SOUTH TO NORTH...WITH 20 POPS SOUTH
FRI/SAT...INCRSG TO SCT AREAWIDE FOR SUN/MON. HAVE ALSO MADE A CHG
TO INTRODUCE LATE NGT COASTAL SHRA BEGINNING FRI NIGHT ACROSS THE
FAR SOUTH AND SPREADING NWD THROUGH THE WEEKEND...IN ANTICIPATION OF
AT LEAST SOME MODEST FRESHENING OF THE ONSHORE FLOW

[ronjon]

Starting to see some convection flaring up just north of Panama now. I think the key to cyclogenesis that the GFS, CMC, & NOGAPS is picking up on is the generally lower pressures in the SW caribbean and very good upper level conditions in the western caribbean with an upper level high anchored right over the top of the disturbance. Very minimal shear forecasted below latitude 20 N.

[cycloneye]

FXUS64 KHGX 261127
AFDHGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
627 AM CDT MON MAY 26 2008

LONG TERM....

MODELS CONTINUE SPIN UP A TROPICAL SYSTEM IN THE EXTREME WESTERN
CARIBBEAN. THE SYSTEM ORIGINATES IN THE PACIFIC ROTATES OVER
HONDURAS INTO THE CARIBBEAN AND THEN EITHER OVER THE YUCATAN OR
THROUGH THE YUCATAN STRAITS...DEPENDING ON WHICH MODEL YOU CHOOSE.
AFTER LOOKING AT THE INITIAL MODEL WINDS AND THE
SCATTEROMETER/SATELLITE WINDS AM FINDING IT VERY HARD TO BELIEVE
THIS SCENARIO. PERHAPS A BIG SURGE OF MOISTURE IS POSSIBLE BUT AM
VERY SKEPTICAL OF ANYTHING VERY ORGANIZED DEVELOPING BY THURSDAY
OR FRIDAY. IN ADDITION THE ECMWF/GFS SOLUTIONS HAVE DIVERGED
DRAMATICALLY BY SATURDAY WITH THE STRENGTH OF THE UPPER RIDGE OVER
TX/NORTHERN MEXICO AND WITH A SYSTEM MOVING INTO PACIFIC NORTHWEST.
WILL BE PARING BACK POPS A LITTLE IN THE EXTENDED AND CONTINUING
THE ABOVE NORMAL TEMPERATURES.

From the Corpus Christi AFD:

.LONG-TERM (TUESDAY NIGHT THROUGH SUNDAY)...LITTLE OF CONSEQUENCE TO
TALK ABOUT FROM THE BEGINNING OF THE PERIOD THROUGH FRIDAY. UPPER
LEVEL HIGH PRESSURE STRETCHING FROM WESTERN MEXICO INTO THE
SOUTHEAST U.S. WILL RETROGRADE WESTWARD AND STRENGTHEN AS IT BECOMES
CENTERED OVER BAJA CALIFORNIA/NORTHWEST MEXICO. A WEAK/MODERATE
ONSHORE FLOW WILL PERSIST ACROSS THE FORECAST AREA WITH DRY
CONDITIONS AND NEAR NORMAL TEMPERATURES EXPECTED. THOUGH LITTLE
CHANGE IN SOUTH TEXAS WEATHER IS EXPECTED NEXT WEEKEND/DAYS 6 AND 7
BEYOND SOMEWHAT HIGHER HIGHER TEMPERATURES DUE TO BUILDING HIGH
PRESSURE ALOFT TO OUR WEST, THE GFS SHOWS A TROPICAL DISTURBANCE
DEVELOPING ON THE EASTERN SIDE OF THE YUCATAN PENINSULA. THIS
FEATURE IS THEN SHOWN TO SLOWLY MOVE NORTHWARD INTO THE SOUTHERN
GULF OF MEXICO. THOUGH THE ECMWF IS NOT SHOWING A FEATURE LIKE THIS,
THE GFS HAS BEEN SHOWING THIS FEATURE ENTERING THE GULF FOR AT LEAST
3 MODEL RUNS AND WILL HAVE TO BE WATCHED IN SUBSEQUENT MODEL RUNS.

[Thunder44]

This is an excerpt from the NHC's 1005 UTC disscussion for the Pacific

UPPER LEVEL MOISTURE REMAINS CONFINED TO THE SRN PORTION OF THE
AREA...OR S OF THE UPPER ANTICYCLONES AND E OF 122W DUE TO THE
EFFECTS OF UPPER LEVEL DIFFLUENCE RESULTING FROM THE POSITIONS
OF THE ANTICYCLONES RELATIVE TO ONE ANOTHER. THIS MOISTURE IS
PRIMARILY TIED TO CONVECTION DESCRIBED ABOVE UNDER ITCZ. THERE
IS SOME INDICATION...AS SEEN ON WATER VAPOR IMAGERY...THAT THE
NRN FRINGE OF THIS MOISTURE IS WORKING ITSELF NWD IN BETWEEN THE
ANTICYCLONES WITH TIME. RECENT AND CURRENT PRES ANALYSES REVEAL
THAT THIS MOISTURE IS RELATED TO AN AREA OF BROAD LOW PRES
WHICH COVERS THE FAR ERN PACIFIC FROM 03N-14N BETWEEN 84W-100W.
COMPUTER MODELS SUGGEST THAT THIS AREA MAY EVENTUALLY CONSOLIDATE
TO FORM A SPECIFIC LOW CENTER DURING THE NEXT FEW DAYS WITH AN
EVENTUAL TRACK TO THE NE AND N. FOR THE TIME BEING...BOTH
SCATTEROMETER DATA AND A FEW SHIP OBSERVATIONS HAVE SHOWN WINDS
IN THE 20-25 KT RANGE WITH DIRECTION FROM SW TO NW WITHIN THIS
AREA. WILL AWAIT FUTURE MODEL RUNS FOR BETTER CONSISTENCY WITH
RESPECT TO POSSIBLE TIMING AND LOCATION OF A LOW PRES SYSTEM IN
THE FAR ERN PACIFIC OCEAN. SCATTERED CLUSTER OF MODERATE TO
STRONG CONVECTION ARE OBSERVED WITHIN 30 NM OF 11N93W...AND
WITHIN 30 NM OF A LINE FROM 12N89W TO 14N90W. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION EXISTS WITHIN 30 NM OF A
LINE FROM 10N86W TO 11N88W.