Global Model Runs for W.Caribbean Early Season Development

[cycloneye]

Corpus Christi AFD:

.LONG TERM (TUESDAY THROUGH SUNDAY)...HIGH AND DRY WITH NOT MUCH
TO ALTER IN THE FORECAST. UPPER LEVEL HIGH PRESSURE SHOULD BEGIN
TO TAKE CONTROL OF AREA THROUGH AT LEAST THE END OF THE
WEEK...THEN MODELS BEGIN TO DIFFER A BIT. LIMITED MOISTURE ON
TUESDAY SHOULD PRECLUDE RAINFALL WITH RIDGE BUILDING IN. FOR
WEDNESDAY...GFS IS SHOWING A SUBTLE MOISTURE SURGE FROM WESTERN
GULF HEADING TOWARD INLAND AREAS...WHICH IT WAS NOT SHOWING
YESTERDAY. CONSIDERING RIDGE OVERHEAD...WILL NOT MENTION RAIN AND
HOLD OFF AS THIS COULD BE ARTIFICIAL/MODEL GENERATED FEATURE
RATHER THAN AN ACTUAL FEATURE. UPPER RIDGE WILL HELP TO BRING
SURFACE BOUNDARY TO CENTRAL TEXAS WITH BEST AVAILABLE
MOISTURE...AND LIFT...TO THE NORTH. ALL WE WILL GET OUT OF THIS IS
LESS WINDS...BUT SLIGHTLY DRIER AIR AND WEAK COOLING OF BOUNDARY
LAYER AND MID LEVEL AIR COULD BRING TEMPS DOWN A COUPLE OF MORE
DEGREES...MORE SEASONABLE. GFS THEN TRIES TO BREAK UPPER RIDGE UP
INTO WESTERN AND EASTERN AREAS...LEAVING A WEAK UPPER REGIME OVER
THE CENTRAL GULF WHILE ECMWF BUILDS A STRONGER RIDGE WITH DEEP
EASTERLY FLOW OVER THE GULF. STILL FEEL WESTERN PORTION OF UPPER
RIDGE...IF GFS IS RIGHT...WILL INFLUENCE SOUTH TEXAS WEATHER AND
BESIDES FORECAST MOISTURE IS QUITE LIMITED (PWATS GENERALLY BELOW
1.5 INCHES)...SO DO NOT EXPECT RAINFALL AT THIS TIME.WHAT REALLY
HAPPENS WITH THE UPPER RIDGE WILL DETERMINE WHERE THE TROPICAL
WAVE THAT MOST LONG-RANGE MODELS ARE SHOWING DECIDES TO GO EARLY
NEXT WEEK...IF THIS WAVE DEVELOPS. SOMETHING TO WATCH.

Houston-Galveston AFD:

000
FXUS64 KHGX 251946
AFDHGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
246 PM CDT SUN MAY 25 2008

.DISCUSSION...
THE PATTERN ALOFT WILL CONTINUE TO GO THROUGH A SUBTLE CHANGE AS
THE RIDGE OVER NORTHERN MEXICO DEVELOPS OVER THE NEXT FEW DAYS. BY
THE MIDDLE OF THE WEEK...SE TX WILL BE UNDER A NORTHWESTERLY FLOW
ALOFT. THIS WILL HELP DRIVE A WEAK FRONT SOUTHWARD...ALTHOUGH THE
GFS AND ECMWF DIFFER ON THE STRENGTH OF THE RIDGE AND HOW FAR
SOUTHWARD THE FRONT WILL REACH" onClick="return popup(this, 'notes')">REACH. THE THINKING HERE IS THAT THE
FRONT WILL PROBABLY GET AT LEAST INTO THE NORTHERN COUNTIES ON
THURSDAY BEFORE WASHING OUT AND WITH THE REMNANTS PUSHING BACK
NORTHWARD FRIDAY.

IN THE SHORT TERM THE NAM WAS DRIER THAN THE GFS. HOWEVER...MODEL
SOUNDINGS FOR MONDAY LOOK SIMILAR TO TODAY AND WILL KEEP ISOLATED
POPS IN MAINLY NORTH OF INTERSTATE 10. WENT WITH THE MODEL
GUIDANCE FOR A DRIER TUESDAY. RAIN CHANCES SHOULD RETURN WEDNESDAY
AND THURSDAY WITH A NORTHWESTERLY FLOW DEVELOPING ALOFT AND THE
FRONT DIPPING INTO THE AREA.

THE GFS AND ECMWF WERE DIFFERING IN THEIR HANDLING OF THE TROPICS
BY DAY SEVEN. THE GFS HAS A WEAKNESS IN THE UPPER RIDGE PRESENT
OVER THE ENTIRE GULF COAST STATES. THE ECMWF HAD A STRONGER RIDGE
IN PLACE FROM MEXICO ALL THE WAY EAST INTO FLORIDA. THE GFS AND
ECMWF DEVELOP A SURFACE LOW IN THE SOUTHERN CARIBBEAN BY THE
UPCOMING WEEKEND...WITH BOTH MODELS THEN GOING IN DIFFERENT
DIRECTIONS WITH THE SYSTEM. GIVEN THE TIME OF YEAR IT IS BEST TO
SAY THAT THE TROPICS BEAR WATCHING.

[Cyclone1]

You heard 'em, they bear watching.

[Eyewall]

Now it looks like all the national weather services on the gulf coast are not on alert to this potential storm. Man who would have thought that we would have been dealing with a potential strom this early in the ball game. I wonder how long it will be before I start to see on our seven day forecast here in New Orleans Gulf Watch.

[Duddy]

You heard 'em, they bear watching.

[micktooth]

NWS Mobile:

.LONG TERM (THURSDAY THROUGH SUNDAY)...THE 5-WAVE PROG SHOWS WEAK
RIDGING REMAINING OVER THE WESTERN AND ALONG THE GULF COASTAL STATES
WHICH WILL TEND TO LIMIT CONVECTIVE DEVELOPMENT THROUGH THE PERIOD.
THE REMNANTS OF THE FRONTAL BOUNDARY DISSIPATE ON THURSDAY...BUT
STILL SUPPORTS SMALL POPS...WITH A SURFACE HIGH OVER THE WESTERN
ATLANTIC PROMOTING A LIGHT ONSHORE FLOW THROUGH SATURDAY. THE GFS
AND ECMWF HAVE A SYSTEM DEVELOPING IN THE WESTERN CARIBBEAN WELL
TIMED FOR THE SEASON WHICH BEGINS JUNE 1ST. BOTH MODELS HAVE HAD
GOOD CONTINUITY OVER THE LAST FEW DAYS WITH THIS FEATURE AND BRING
THE SYSTEM JUST NORTH OF THE YUCATAN PENINSULA ON SUNDAY. THIS
SYSTEM WARRANTS CLOSE SCRUTINY PER HPC LONG RANGE DISCUSSION.

[Eyewall]

The weird thing about this potential storm is that most of the time when these stormes develop this early in the caribbean or gulf they head toward florida. But this one looks like to want's to possibly go against history.

[jimvb]

So it looks like we are going to get a Bear Stearns - er I mean a Bear Storm, next week. I thought for sure that this situation was bearish. I just hope it doesn't have the scope of the Bear Stearns disaster.

[micktooth]

Tampa NWS:

LONG TERM (TUESDAY NIGHT - SUNDAY)...NOT MUCH TO TALK ABOUT IN THE
EXTENDED PORTION OF THE FORECAST. WE WILL CONTINUE TO DOWNPLAY THE
AREA OF LOW PRESSURE THAT THE GFS TAKES ACROSS THE YUCATAN PENINSULA
NEXT SUNDAY. THE ECMWF HAS A SIMILAR TRACK...BUT MAINTAINS ENOUGH
RIDGING TO KEEP THE PRESSURE GRADIENT SOUTH OF OUR REGION. THE GFS
REALLY TIGHTENS UP THE GRADIENT OFFSHORE SOUTH FLORIDA LATE IN THE
PERIOD...WHICH LOOKS A BIT UNREALISTIC.

[Eyewall]

I know some of the modles have shown this possibly becoming a cat 1 hurricane yesterday. And if this were to happen I hope this does not turn out to be one of these stormes that has four gulf coast states on the run like hurricane Ivan.

[Aric Dunn]

melbourne.. nws

BOTH THE GFS AND ECM KEEP DEEP LAYER
MOISTURE ON THE NRN FLANK OF A WWD MOVING CARIBBEAN DISTURBANCE
(WHICH ISN`T LIKELY TO BE QUITE AS ROBUST AS THE MODELS SUGGEST) AT
BAY...LIFTING IT UP ONLY ACROSS THE SRN THIRD OF THE PENINSULA BY
FRI/SAT. AS SUCH

[Cyclone1]

I know some of the modles have shown this possibly becoming a cat 1 hurricane yesterday. And if this were to happen I hope this does not turn out to be one of these stormes that has four gulf coast states on the run like hurricane Ivan.

Intensity is the most unpredictable thing in a storm. We can't predict perfectly it 24 hours out, much less a week. Those models are used basically for area.

[Aric Dunn]

miami.... nws

INTO THE END OF THE WEEK AND INTO NEXT WEEKEND... SOUTHEAST FLOW
OVER S FL IS EXPECTED AROUND A RIDGE OVER THE ATLANTIC WHICH WOULD
ALLOW DEEP MOISTURE TO RETURN TO THE AREA. THIS WILL CAUSE POPS
TO CLIMB TO AROUND CLIMO OR POSSIBLY OVER AS TROPICAL MOISTURE
STREAMS OUT OF THE CARIBBEAN.

[Aric Dunn]

new orleans .. nws

THIS WEEKEND...THE GFS...ECMWF...AND CMC CONTINUE A PERSISTENT
TREND OF FORECASTING SOME TYPE OF TROPICAL CYCLONE IN THE AREA
FROM THE WESTERN CARIBBEAN SEA TO THE YUCATAN PENINSULA AREA
FRIDAY INTO SATURDAY. IT IS STILL TOO EARLY TO KNOW IF DEVELOPMENT
WOULD OCCUR...OR WHERE ANY SYSTEM WOULD END UP GOING EARLY NEXT
WEEK. REFER TO HPC EXTENDED FORECAST DISCUSSIONS FOR MORE
DETAILS. FOR OUR WEATHER...IT LOOKS IT WILL BE MOSTLY DRY AND
SEASONABLY WARM TO HOT NEXT WEEKEND. 22


lake charles.... nws

.LONG TERM...LATER NEXT WEEK, BOTH THE GFS AND THE ECMWF CONTINUE
TO DEVELOP A COLD CORE LARGE SCALE AND STACKED LOW PRESSURE SYSTEM
NEAR THE YUCATAN. RIDGING AT THE SURFACE WILL BUILD ON THE OUTER
PORTION OF THIS SYSTEM ALONG THE GULF COAST. INCLUDED MINIMAL
PRECIP CHANCES NEXT WEEKEND AS MOISTURE INCREASES INTO AN OUTER
CONVERGENCE BAND. THIS IS STILL VERY PRELIMINARY SINCE THE GFS
DEEPENS THE LOW TO 998HPA AT THE SURFACE NORTH OF THE YUCATAN A
WEEK DOWN THE ROAD. I`M FAVORING THE EURO WHICH HAS A MUCH WEAKER
1006HPA LOW IN THE BAY OF CAMPECHE. IT SHOULD BE NOTED THAT BOTH
MODELS MORPH THE SYSTEM INTO A HYBRED WARM CORE LOW NEXT WEEKEND.

[KWT]

Well the extended discussions pretty much state that whilst there is a chance it could happen its still too early to make a decent call.

Anyway 18z GFS coming out shortly anyway.

[Opal storm]

[Duddy]

new orleans .. nws

THIS WEEKEND...THE GFS...ECMWF...AND CMC CONTINUE A PERSISTENT
TREND OF FORECASTING SOME TYPE OF TROPICAL CYCLONE IN THE AREA
FROM THE WESTERN CARIBBEAN SEA TO THE YUCATAN PENINSULA AREA
FRIDAY INTO SATURDAY. IT IS STILL TOO EARLY TO KNOW IF DEVELOPMENT
WOULD OCCUR...OR WHERE ANY SYSTEM WOULD END UP GOING EARLY NEXT
WEEK. REFER TO HPC EXTENDED FORECAST DISCUSSIONS FOR MORE
DETAILS. FOR OUR WEATHER...IT LOOKS IT WILL BE MOSTLY DRY AND
SEASONABLY WARM TO HOT NEXT WEEKEND. 22


lake charles.... nws

.LONG TERM...LATER NEXT WEEK, BOTH THE GFS AND THE ECMWF CONTINUE
TO DEVELOP A COLD CORE LARGE SCALE AND STACKED LOW PRESSURE SYSTEM
NEAR THE YUCATAN. RIDGING AT THE SURFACE WILL BUILD ON THE OUTER
PORTION OF THIS SYSTEM ALONG THE GULF COAST. INCLUDED MINIMAL
PRECIP CHANCES NEXT WEEKEND AS MOISTURE INCREASES INTO AN OUTER
CONVERGENCE BAND. THIS IS STILL VERY PRELIMINARY SINCE THE GFS
DEEPENS THE LOW TO 998HPA AT THE SURFACE NORTH OF THE YUCATAN A
WEEK DOWN THE ROAD. I`M FAVORING THE EURO WHICH HAS A MUCH WEAKER
1006HPA LOW IN THE BAY OF CAMPECHE. IT SHOULD BE NOTED THAT BOTH
MODELS MORPH THE SYSTEM INTO A HYBRED WARM CORE LOW NEXT WEEKEND.

How could a low that may originate in the Bay of Campeche be a cold core?

[Duddy]

[Aric Dunn]

new orleans .. nws

THIS WEEKEND...THE GFS...ECMWF...AND CMC CONTINUE A PERSISTENT
TREND OF FORECASTING SOME TYPE OF TROPICAL CYCLONE IN THE AREA
FROM THE WESTERN CARIBBEAN SEA TO THE YUCATAN PENINSULA AREA
FRIDAY INTO SATURDAY. IT IS STILL TOO EARLY TO KNOW IF DEVELOPMENT
WOULD OCCUR...OR WHERE ANY SYSTEM WOULD END UP GOING EARLY NEXT
WEEK. REFER TO HPC EXTENDED FORECAST DISCUSSIONS FOR MORE
DETAILS. FOR OUR WEATHER...IT LOOKS IT WILL BE MOSTLY DRY AND
SEASONABLY WARM TO HOT NEXT WEEKEND. 22


lake charles.... nws

.LONG TERM...LATER NEXT WEEK, BOTH THE GFS AND THE ECMWF CONTINUE
TO DEVELOP A COLD CORE LARGE SCALE AND STACKED LOW PRESSURE SYSTEM
NEAR THE YUCATAN. RIDGING AT THE SURFACE WILL BUILD ON THE OUTER
PORTION OF THIS SYSTEM ALONG THE GULF COAST. INCLUDED MINIMAL
PRECIP CHANCES NEXT WEEKEND AS MOISTURE INCREASES INTO AN OUTER
CONVERGENCE BAND. THIS IS STILL VERY PRELIMINARY SINCE THE GFS
DEEPENS THE LOW TO 998HPA AT THE SURFACE NORTH OF THE YUCATAN A
WEEK DOWN THE ROAD. I`M FAVORING THE EURO WHICH HAS A MUCH WEAKER
1006HPA LOW IN THE BAY OF CAMPECHE. IT SHOULD BE NOTED THAT BOTH
MODELS MORPH THE SYSTEM INTO A HYBRED WARM CORE LOW NEXT WEEKEND.

How could a low that may originate in the Bay of Campeche be a cold core?

not saying they are right i will have to look at the upper levels.. but the location of a system i.e in the lower latitudes or higher does not determine its Phase. rather its a completly set up for both types warm core hybird/ cold core. to put it simply in a warm core the closer you get to the low pressure the warmer the air and higher the dew point. and in In a cold core low, we have relatively cold air in the lower layers and relatively warm air aloft

[NDG]

new orleans .. nws

THIS WEEKEND...THE GFS...ECMWF...AND CMC CONTINUE A PERSISTENT
TREND OF FORECASTING SOME TYPE OF TROPICAL CYCLONE IN THE AREA
FROM THE WESTERN CARIBBEAN SEA TO THE YUCATAN PENINSULA AREA
FRIDAY INTO SATURDAY. IT IS STILL TOO EARLY TO KNOW IF DEVELOPMENT
WOULD OCCUR...OR WHERE ANY SYSTEM WOULD END UP GOING EARLY NEXT
WEEK. REFER TO HPC EXTENDED FORECAST DISCUSSIONS FOR MORE
DETAILS. FOR OUR WEATHER...IT LOOKS IT WILL BE MOSTLY DRY AND
SEASONABLY WARM TO HOT NEXT WEEKEND. 22


lake charles.... nws

.LONG TERM...LATER NEXT WEEK, BOTH THE GFS AND THE ECMWF CONTINUE
TO DEVELOP A COLD CORE LARGE SCALE AND STACKED LOW PRESSURE SYSTEM
NEAR THE YUCATAN. RIDGING AT THE SURFACE WILL BUILD ON THE OUTER
PORTION OF THIS SYSTEM ALONG THE GULF COAST. INCLUDED MINIMAL
PRECIP CHANCES NEXT WEEKEND AS MOISTURE INCREASES INTO AN OUTER
CONVERGENCE BAND. THIS IS STILL VERY PRELIMINARY SINCE THE GFS
DEEPENS THE LOW TO 998HPA AT THE SURFACE NORTH OF THE YUCATAN A
WEEK DOWN THE ROAD. I`M FAVORING THE EURO WHICH HAS A MUCH WEAKER
1006HPA LOW IN THE BAY OF CAMPECHE. IT SHOULD BE NOTED THAT BOTH
MODELS MORPH THE SYSTEM INTO A HYBRED WARM CORE LOW NEXT WEEKEND.

How could a low that may originate in the Bay of Campeche be a cold core?

not saying they are right i will have to look at the upper levels.. but the location of a system i.e in the lower latitudes or higher does not determine its Phase. rather its a completly set up for both types warm core hybird/ cold core. to put it simply in a warm core the closer you get to the low pressure the warmer the air and higher the dew point. and in In a cold core low, we have relatively cold air in the lower layers and relatively warm air aloft

Lake Charles had to make a mistake, or carelessly did not look at the upper level set up, because by no means if it develops will be a cold core low, if anything it will have a nice upper level ridge develop very close to it, indicated by all models.

By the way in a cold core system there could also be warm air at the surface but colder air aloft the closer you get to the center of surface pressure, many times with an upper level on top, in a warm core (tropical system) you have warmer air in all levels of the atmosphere the closer you get to the center with an anticyclone circulation or upper level ridge on top.

[Meso]

GFS @ 114 hours.. Low entering caribbean...

Bed time