Tropical Wave In Eastern Caribbean

[GeneratorPower]

IR is now showing the whispy thin streaks that precede complete poof.

[KWT]

Convection has indeed weakened though it hasn't quite totally gone yet, does look like its now being sheared quite a bit though as was expected.

[Gustywind]

000
AWCA82 TJSJ 130937
RWSVI

WEATHER SUMMARY FOR THE U.S. VIRGIN ISLANDS
NATIONAL WEATHER SERVICE SAN JUAN PR
537 AM AST FRI JUN 13 2008
SKIES WERE PARTLY CLOUDY ACROSS THE ISLANDS AS CLOUDS AND PASSING
SHOWERS MOVED ACROSS THE SURROUNDING WATERS AND AFFECTED PARTS OF
THE ISLANDS FROM TIME TO TIME. NO SIGNIFICANT RAINFALL AMOUNTS WERE
HOWEVER DETECTED BY THE DOPPLER WEATHER RADAR OR REPORTED DURING
THE OVERNIGHT HOURS. THE WINDS WERE FROM THE EAST SOUTHEAST AT 5
TO 15 MPH.

AN ELONGATED WEAK TROPICAL WAVE THAT EXTENDS FROM NORTHERN
COLOMBIA NORTHEASTWARD TO THE LOCAL OFF SHORE ATLANTIC WATERS
IS MOVING ACROSS THE LOCAL ISLANDS EARLY THIS MORNING. THIS IS EXPECTED
TO AFFECT THE FORECAST AREA...AS IT MOVES ACROSS THE LOCAL AREA
FOR MUCH OF THE MORNING HOURS. A SECOND AND BETTER DEFINED
TROPICAL WAVE WILL QUICKLY FOLLOW AND MOVE ACROSS THE LOCAL
ISLANDS THIS AFTERNOON INTO LATE THIS EVENING OR EARLY SATURDAY
MORNING...RESULTING IN AN OVERALL INCREASE IN CLOUDINESS...SHOWERS...
AND THUNDERSTORMS WITH GUSTY WINDS ACROSS THE LOCAL ISLANDS AND
REGIONAL WATERS.

SHOWERS AND THUNDERSTORMS WILL DEVELOP ACROSS THE EASTERN
CARIBBEAN WATERS SURROUNDING THE VIRGIN ISLANDS...AND WILL LATER
SPREAD ACROSS PUERTO RICO. BY THIS AFTERNOON...THE MOISTURE ASSOCIATED
WITH THE TROPICAL WAVE...ENHANCED BY A WEAK UPPER LEVEL TROUGH
JUST NORTH OF THE ISLANDS...WILL LEAD TO THE DEVELOPMENT OF
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE U.S.
VIRGIN ISLANDS AND LOCAL COASTAL WATERS. DUE TO THE ANTICIPATED
WEATHER CONDITIONS...THERE IS A CHANCE FOR SOME LOCALIZED URBAN
AND GUTS FLOODING OVER PARTS OF THE ISLANDS DURING THE AFTERNOON
AND EARLY EVENING HOURS.

ACROSS THE LOCAL WATERS...WINDS...SEAS...AND THUNDERSTORM ACTIVITY
WILL INCREASE ACROSS THE REGIONAL WATERS LATER TODAY THROUGH SATURDAY
MORNING IN ASSOCIATION WITH THE PASSAGE OF THE TROPICAL WAVE. MARINERS
CAN EXPECT GUSTY WINDS...LOCALLY HIGHER WAVES...LIGHTNING
STRIKES...AND TEMPORARILY HEAVY DOWNPOURS AS THESE STORMS MOVE
ACROSS OUR LOCAL WATERS.

$$

[KWT]

Convection has continued to weaken with this wave with the only moderate area of convection being now a little bit behind the wave axis.

[Gustywind]

Yeah KWT agree, a cluster of moderate convection east of Barbadosg is persisting...
http://www.meteo.fr/temps/domtom/antill ... Tagant.jpg
But will be quicly sheared i tkink given the higher shear values east of the east carib islands 20 to 40 Kts...
http://cimss.ssec.wisc.edu/tropic/real- ... g8shr.html
Whereas i have seen better defined waves sweept earlier than this one with the same values of shear, but the shear tendency will it play a role?, winds seems abatting a little and why not... maybe a slight window to see some more organized convection and a better sat pic appareance... during next hours?!:
http://cimss.ssec.wisc.edu/tropic/real- ... g8sht.html

[KWT]

Yep the shear will probably help to really weaken the convection just to the east of the axis as well. Still if it can keep its wave axis then it may end up needing to be watched 3-5 days down the road.

[bvigal]

It looks much less vigorous this morning! Will be interesting to see how this pans out.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
601 AM AST FRI JUN 13 2008

.DISCUSSION...MOISTURE AND INSTABILITY ASSOCIATED WITH TWO
TROPICAL WAVES ACROSS THE CARIBBEAN WILL INTERACT FAVORABLY WITH
WLY FLOW ALOFT TO PRODUCE ACTIVE WEATHER TODAY THROUGH SATURDAY
MIDDAY...

Eagerly awaiting NHC's 8am discussion.

[Frank2]

gatorcane, perhaps the subject line needs to be downgraded to a open wave...

LOL

[Gustywind]

we will see what pan's out during the next 6 hours...if the trend is on weakning system or not..

[KWT]

Well looking at the loops it threw out quite a few outflow boundaries about 6-9hrs ago so no wonder the convection has really decreased a lot.

[bvigal]

Hmm, which one of these to believe? (note tropical wave placement, northern extent, and low emerging off Columbia along wave)
Maybe TBK and JC need to talk...

[gatorcane]

gatorcane, perhaps the subject line needs to be downgraded to a open wave...

LOL

Indeed, I just edited it.

[KWT]

Not sure to be honest bvigal we will have to wait and see, going to have to wastch the SW Caribbean region again though when these two tropical waves pass through, esp given there is a weakness now to allow anything to the north.

[Gustywind]

Where is the TWD? what'up?? , very late today, because we're friday 13th lol

[bvigal]

000
AXNT20 KNHC 131327
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI JUN 13 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND
RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ESTIMATED ALONG 23W TO THE S OF 18N AND
MOVING W AT 15-20 KT AND POSITION SUGGESTED IN LATEST ANIMATION
OF SSMI-DERIVED TPW. ONLY A FEW CELLS ARE NOTED ALONG THE WAVE
AXIS AT 09.5N.

A TROPICAL WAVE IS ALONG 60W S OF 19N MOVING W AT 15-20 KT. THE
WAVE IS WELL DEPICTED IN THE MOISTURE PRODUCTS AND E CARIBBEAN
ISLANDS SURFACE OBSERVATIONS. SCATTERED TSTMS ARE NOTED WITHIN
150 NM OF AXIS AT 15N BUT HAVE BEEN DECREASING IN INTENSITY FOR
THE PAST 6 HOURS.

A TROPICAL WAVE IS ALONG 67W-68W AND EXTENDS AS FAR N AS PUERTO
RICO. THIS WAVE SEEMS TO BE LOSING IDENTITY WITHIN A LARGER AREA
OF INCREASED EASTERLY WINDS. ONLY ISOLATED LIGHT SHOWERS ARE
NOTED ALONG THE WAVE AXIS AT 15.5N.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 09N13W TO 01N31W TO 02N40W TO
01S45W. ISOLATED MODERATE TO STRONG CONVECTION IS NOTED WITHIN
90 NM EITHER SIDE OF LINE 10N20W TO 04N35W AND FROM 02S TO 04N
BETWEEN 35W AND 52W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER TROUGH EXTENDS S ACROSS THE MISSISSIPPI VALLEY INTO THE
AREA AT 30N90W AND CONTINUING S INTO A MID TO UPPER LEVEL
CYCLONE CENTERED NEAR 23N95W WHICH IN TURN IS DRIFTING W WITH
TIME.
AT THE LOW LEVELS A TROUGH IS ANALYZED FROM 18N95W TO 26N90W. AN
UPPER ANTICYCLONE NEAR 15N89W HAS AN UPPER RIDGE EXTENDING N
ACROSS THE EASTERN GULF OF MEXICO TO A CREST NEAR 30N88W. DRY
UPPER AIR IS NOTED W OF THE DESCRIBED TROUGH AND INTO THE SW
PERIPHERY OF THE CYCLONE. UPPER DIFFLUENCE E OF THE
CYCLONE...AND UNDER THE RIDGE...ENHANCED CONVECTION OVER THE
YUCATAN PENINSULA THU WITH THE RESULTANT DEBRIS MOISTURE NOW
SPREADING N UNDER THE RIDGE...BASICALLY DOMINATING THE UPPER
LEVELS OF THE GULF E OF 92W AND ACROSS SW FLORIDA.

CARIBBEAN...
A BROAD UPPER TROUGH EXTENDS S OVER THE N CENTRAL CARIBBEAN.
A BROAD E TO W UPPER RIDGE DOMINATES THE UPPER LEVELS OF THE
CARIBBEAN ELSEWHERE E OF 82W. UPPER DEBRIS MOISTURE ORIGINATING
FROM INTENSE TSTMS THAT FLARED EARLIER OVER THE YUCATAN
PENINSULA...AND OVER CENTRAL AMERICA...IS NOW STREAMING E OVER
THE N CENTRAL AND SW CARIBBEAN. A BAND OF DRY UPPER AIR IS NOTED
FROM COLOMBIA TO PUERTO RICO AND IS SUPPRESSING CONVECTION OVER
THE S CENTRAL PORTION. AT THE LOW LEVELS THE WESTERN EDGE OF AN
EASTERLY WIND SURGE APPEARS TO BE ALONG 75W WITH ONLY TRADE WIND
CUMULUS OBSERVED BETWEEN 65W AND 80W. A TROPICAL WAVE IS MOVING
W ACROSS THE EASTERN CARIBBEAN ISLANDS ACCOMPANIED BY A LARGE
CLUSTER OF TSTMS ALONG THE WAVE AT 15N BUT DECREASING THE PAST
FEW HOURS.

ATLANTIC...
AN UPPER LEVEL CYCLONE NEAR 28N76W HAS A TROUGH EXTENDING S
ACROSS THE SE BAHAMAS INTO THE CARIBBEAN NEAR 18N74W. DEBRIS
MOISTURE...SOME ORIGINATING OVER FL ON THU AFTERNOON...IS NOTED
OVER THE SW SEMICIRCLE OF THE CYCLONE...ROUGHLY W OF LINE 20N66W
TO 30N76W. A FEW HEAVY SHOWERS AND TSTMS ARE STILL FLARING
WITHIN THIS LARGE MOISTURE AREA...MOSTLY WITHIN 90 NM OF 22N73W.
THE SUBTROPICAL CENTRAL ATLC IS DOMINATED BY THE SOUTHERN END OF
A LONG WAVE TROUGH BETWEEN 70W AND 35W WITH AN UPPER CYCLONE
FILLING AS IT MOVES E NEAR 25N58W. AN ASSOCIATED SURFACE COLD
FRONT LIES ALONG 31N32W TO 27N46W THEN IT BECOMES STATIONARY
ALONG 28N55W TO 25N72W. A SECOND COLD FRONT IS APPROACHING THE
AREA AND IS CURRENTLY PASSING THROUGH BERMUDA. THE UPPER LEVELS
OF THE SUBTROPICAL EASTERN ATLC IS ALSO DOMINATED BY A TROUGH
ALONG 32N03W TO 24N20W TO 20N34W. AN UPPER RIDGE EXTENDS W OFF
THE AFRICAN COAST ALONG 17N15W TO A SHARP CREST AT 12N42W. UPPER
DIFFLUENCE IS ENHANCING CONVECTION DESCRIBED IN THE ITCZ
DISCUSSION ABOVE.

$$
NELSON

[Gustywind]

000
AXNT20 KNHC 131327
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI JUN 13 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND
RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ESTIMATED ALONG 23W TO THE S OF 18N AND
MOVING W AT 15-20 KT AND POSITION SUGGESTED IN LATEST ANIMATION
OF SSMI-DERIVED TPW. ONLY A FEW CELLS ARE NOTED ALONG THE WAVE
AXIS AT 09.5N.

A TROPICAL WAVE IS ALONG 60W S OF 19N MOVING W AT 15-20 KT. THE
WAVE IS WELL DEPICTED IN THE MOISTURE PRODUCTS AND E CARIBBEAN
ISLANDS SURFACE OBSERVATIONS. SCATTERED TSTMS ARE NOTED WITHIN
150 NM OF AXIS AT 15N BUT HAVE BEEN DECREASING IN INTENSITY FOR
THE PAST 6 HOURS.

A TROPICAL WAVE IS ALONG 67W-68W AND EXTENDS AS FAR N AS PUERTO
RICO. THIS WAVE SEEMS TO BE LOSING IDENTITY WITHIN A LARGER AREA
OF INCREASED EASTERLY WINDS. ONLY ISOLATED LIGHT SHOWERS ARE
NOTED ALONG THE WAVE AXIS AT 15.5N.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 09N13W TO 01N31W TO 02N40W TO
01S45W. ISOLATED MODERATE TO STRONG CONVECTION IS NOTED WITHIN
90 NM EITHER SIDE OF LINE 10N20W TO 04N35W AND FROM 02S TO 04N
BETWEEN 35W AND 52W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER TROUGH EXTENDS S ACROSS THE MISSISSIPPI VALLEY INTO THE
AREA AT 30N90W AND CONTINUING S INTO A MID TO UPPER LEVEL
CYCLONE CENTERED NEAR 23N95W WHICH IN TURN IS DRIFTING W WITH
TIME.
AT THE LOW LEVELS A TROUGH IS ANALYZED FROM 18N95W TO 26N90W. AN
UPPER ANTICYCLONE NEAR 15N89W HAS AN UPPER RIDGE EXTENDING N
ACROSS THE EASTERN GULF OF MEXICO TO A CREST NEAR 30N88W. DRY
UPPER AIR IS NOTED W OF THE DESCRIBED TROUGH AND INTO THE SW
PERIPHERY OF THE CYCLONE. UPPER DIFFLUENCE E OF THE
CYCLONE...AND UNDER THE RIDGE...ENHANCED CONVECTION OVER THE
YUCATAN PENINSULA THU WITH THE RESULTANT DEBRIS MOISTURE NOW
SPREADING N UNDER THE RIDGE...BASICALLY DOMINATING THE UPPER
LEVELS OF THE GULF E OF 92W AND ACROSS SW FLORIDA.

CARIBBEAN...
A BROAD UPPER TROUGH EXTENDS S OVER THE N CENTRAL CARIBBEAN.
A BROAD E TO W UPPER RIDGE DOMINATES THE UPPER LEVELS OF THE
CARIBBEAN ELSEWHERE E OF 82W. UPPER DEBRIS MOISTURE ORIGINATING
FROM INTENSE TSTMS THAT FLARED EARLIER OVER THE YUCATAN
PENINSULA...AND OVER CENTRAL AMERICA...IS NOW STREAMING E OVER
THE N CENTRAL AND SW CARIBBEAN. A BAND OF DRY UPPER AIR IS NOTED
FROM COLOMBIA TO PUERTO RICO AND IS SUPPRESSING CONVECTION OVER
THE S CENTRAL PORTION. AT THE LOW LEVELS THE WESTERN EDGE OF AN
EASTERLY WIND SURGE APPEARS TO BE ALONG 75W WITH ONLY TRADE WIND
CUMULUS OBSERVED BETWEEN 65W AND 80W. A TROPICAL WAVE IS MOVING
W ACROSS THE EASTERN CARIBBEAN ISLANDS ACCOMPANIED BY A LARGE
CLUSTER OF TSTMS ALONG THE WAVE AT 15N BUT DECREASING THE PAST
FEW HOURS.

ATLANTIC...
AN UPPER LEVEL CYCLONE NEAR 28N76W HAS A TROUGH EXTENDING S
ACROSS THE SE BAHAMAS INTO THE CARIBBEAN NEAR 18N74W. DEBRIS
MOISTURE...SOME ORIGINATING OVER FL ON THU AFTERNOON...IS NOTED
OVER THE SW SEMICIRCLE OF THE CYCLONE...ROUGHLY W OF LINE 20N66W
TO 30N76W. A FEW HEAVY SHOWERS AND TSTMS ARE STILL FLARING
WITHIN THIS LARGE MOISTURE AREA...MOSTLY WITHIN 90 NM OF 22N73W.
THE SUBTROPICAL CENTRAL ATLC IS DOMINATED BY THE SOUTHERN END OF
A LONG WAVE TROUGH BETWEEN 70W AND 35W WITH AN UPPER CYCLONE
FILLING AS IT MOVES E NEAR 25N58W. AN ASSOCIATED SURFACE COLD
FRONT LIES ALONG 31N32W TO 27N46W THEN IT BECOMES STATIONARY
ALONG 28N55W TO 25N72W. A SECOND COLD FRONT IS APPROACHING THE
AREA AND IS CURRENTLY PASSING THROUGH BERMUDA. THE UPPER LEVELS
OF THE SUBTROPICAL EASTERN ATLC IS ALSO DOMINATED BY A TROUGH
ALONG 32N03W TO 24N20W TO 20N34W. AN UPPER RIDGE EXTENDS W OFF
THE AFRICAN COAST ALONG 17N15W TO A SHARP CREST AT 12N42W. UPPER
DIFFLUENCE IS ENHANCING CONVECTION DESCRIBED IN THE ITCZ
DISCUSSION ABOVE.

$$
NELSON

Tkanks Bvigal

[Gustywind]

000
AWCA82 TJSJ 131530
RWSVI

WEATHER SUMMARY FOR THE U.S. VIRGIN ISLANDS
NATIONAL WEATHER SERVICE SAN JUAN PR
1130 AM AST FRI JUN 13 2008

MOSTLY SUNNY SKIES WERE OBSERVED ACROSS THE U.S. VIRGIN ISLANDS
THIS MORNING. DOPPLER WEATHER RADAR DETECTED ISOLATED SHOWERS
OVER THE COASTAL WATERS...WITH NO PRECIPITATION OVER LAND. THE
WINDS HAVE BEEN GENERALLY OUT OF THE EAST SOUTHEAST AT 10 TO 20 MPH.

SLIGHTLY DRIER AIR BEHIND A TROPICAL WAVE WEST OF THE LOCAL AREA THIS
MORNING IS EVIDENT IN LATEST SATELLITE IMAGERY. HOWEVER...EXPECT
LINGERING MOISTURE COMBINED WITH LOCAL EFFECTS TO RESULT IN
ISOLATED SHOWERS ACROSS THE U.S. VIRGIN ISLANDS AND SURROUNDING
WATERS TODAY. BY THE EARLY EVENING HOURS...EXPECT MORE NUMEROUS
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SECOND TROPICAL
WAVE...TO DEVELOP ACROSS THE EASTERN CARIBBEAN WATERS AND U.S.
VIRGIN ISLANDS. THIS INCREASED SHOWER ACTIVITY IS EXPECTED TO
CONTINUE INTO SATURDAY...WITH PERIODS OF HEAVY RAIN...GUSTY
WINDS...AND LOCALIZED FLOODING.

ACROSS THE LOCAL WATERS...WINDS...SEAS...AND THUNDERSTORM ACTIVITY
WILL INCREASE LATE THIS AFTERNOON THROUGH SATURDAY IN
ASSOCIATION WITH THE PASSAGE OF THE TROPICAL WAVE.

$$

SR
I've got moderate showers and thunder is roaring often, no winds and lightning, maybe 5 millimeters on my area nothing much for the moment.

[HUC]

Heavy rain shower with thunder in Basse-Terre;we got a wind surge yersterday night,since3 am,when the wind increased to 25kts. No change in direction finally,always SEst...

[Meso]

I wonder if this is the wave the NAM moves NW and then closes off in 84 hours

[KWT]

Hmmm it could well be spwaned from the wave complex, given its current location and that time span it does appear to fit as well. We will have to wait and see won't we, the NAM can be a little hasty in closing off circulations with any tropical system I've noticed.