[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 030549
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI JUN 03 2005

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...TROPICAL WAVES...

E ATLC TROPICAL WAVE WAS INTRODUCED ALONG 32W S OF 12N MOVING W
10-15 KT BASED ON DAKAR SOUNDING AND QUIKSCAT DATA. WAVE IS
EMBEDDED BENEATH AN MID/UPPER LEVEL RIDGE THAT EXTENDS W ACROSS
THE TROPICAL ATLC...THUS ONLY A WEAK SIGNATURE CAN BE OBSERVED.
NO ASSOCIATED DEEP CONVECTION.

CENTRAL ATLC TROPICAL WAVE WAS RELOCATED ALONG 55W S OF 17N
MOVING W 20-25 KT BASED ON THE SOUNDING AT CAYENNE. FAIRLY
WELL-DEFINED MID-LEVEL CIRCULATION IS OBSERVED ALTHOUGH WAVE IS
EMBEDDED BENEATH AN WESTERN EDGE OF THE MID/UPPER LEVEL RIDGE
THAT EXTENDS W ACROSS THE TROPICAL ATLC. WAVE IS ENHANCING
CONVECTION WITHIN THE ITCZ THAT IS BEING DRAWN N TO 10N.
SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 90/120 NM OF LINE
FROM 8N44W-10N49W-11N55W.

E CARIBBEAN TROPICAL WAVE WAS RELOCATED ALONG 68W/69W S OF 17N
MOVING W 15-20 KT. THE WAVE HAS MOVED FAR ENOUGH W OF THE CLOSED
MID/UPPER LOW OVER THE E CARIBBEAN THAT HAD BEEN SHEARING THE
SYSTEM THAT THE LOW-LEVEL SIGNATURE CAN NOW BE SEEN ON SATELLITE
IMAGERY...THUS THE JUSTIFICATION FOR THE RELOCATION. DUE TO
LIMITED MOISTURE AND THE UPPER AIR PATTERN...ONLY ISOLATED LOW
LEVEL SHOWERS DOT THE AREA.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 13N15W 9N21W 8N30W 6N34W 6N42W
11N53W 8N57W 7N60W. IN ADDITION TO THE CONVECTION ASSOCIATED
WITH THE WAVE ALONG 55W...SCATTERED MODERATE/ISOLATED STRONG
CONVECTION IS WITHIN 75 NM OF THE AXIS FROM 41W-44W AND WITHIN
120 NM N OF THE AXIS FROM 20W-25W. SCATTERED MODERATE WITH
CLUSTERS OF ISOLATED STRONG CONVECTION HAS MOVED OFF THE COAST
OF AFRICA AND NOW COVERS THE AREA FROM 5N-11N BETWEEN 11W-18W.
CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 150 NM S OF
THE AXIS FROM 20W-28W.

...DISCUSSION...

GULF OF MEXICO...
SHARP MID/UPPER LEVEL TROUGH CONTINUES TO MOVE SLOWLY E ACROSS
THE CENTRAL GULF WITH AN ELONGATED CUT-OFF LOW N OF THE YUCATAN
PENINSULA NEAR 25N87W. BROAD UPPER DIFFLUENCE E OF THE TROUGH
AXIS HAS SPREAD MID/HIGH CLOUDS OVER THE E GULF AND FLORIDA INTO
THE W ATLC...AND ALSO MADE THE REGION QUITE CONDUCIVE FOR HEAVY
RAIN AND ISOLATED THUNDERSTORMS. THIS PATTERN IS KEEPING WET
WEATHER ACROSS THIS AREA WITH SCATTERED SHOWERS AND POSSIBLE
EMBEDDED THUNDERSTORMS TO CONTINUE E OF THE UPPER TROUGH AXIS
DURING THE EARLY MORNING HOURS. A WEAK SURFACE TROUGH LIES
ACROSS THE CENTRAL GULF ALONG 28N86W TO 23N93W. THE UPPER TROUGH
IS EXPECTED TO LINGER OVER THE AREA TODAY WILL THEN WEAKEN AND
BE ABSORBED BY A MUCH LARGE LONGWAVE TROUGH FROM OVER THE
CENTRAL U.S. STARTING ON SAT. DEEP LAYERED MOISTURE AND THE E
GULF TROUGH WILL CONTINUE TO PRODUCE HEAVY RAINS AND
THUNDERSTORMS ACROSS FLORIDA TODAY...BUT THEN THE PATTERN SHOULD
BEGIN TO SHIFT TO A SLIGHTLY DRIER SCENARIO IN WHICH THE NORMAL
DAYTIME AFTERNOON THUNDERSTORMS OCCURRING OVER FLORIDA DURING
THE WEEKEND. THE W HALF OF THE GULF IS DOMINATED BY MOSTLY CLEAR
SKIES AS THE RESULT OF MODERATE/STRONG SUBSIDENCE IN THE
MID/UPPER LEVELS BEHIND THE TROUGH...BUT HIGH DEBRIS CLOUDS ARE
MOVING OVER THE FAR W GULF FROM SHOWERS/THUNDERSTORMS THAT
OCCURRED EARLY THIS EVENING OVER TEXAS AND E MEXICO.

CARIBBEAN...
MID/UPPER LEVEL TROUGH FROM THE GULF EXTENDS S OVER THE YUCATAN
AND HONDURAS WITH A HIGHLY AMPLIFIED RIDGE TO THE E EXTENDING
FROM PANAMA ACROSS E CUBA NEAR 21N77W. THIS SCENARIO IS
PROVIDING ENOUGH UPPER DIVERGENCE TO THE E OF THE TROUGH TO
SUPPORT SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 11N W OF
77W TO INLAND OVER THE YUCATAN AND PORTIONS OF CENTRAL AMERICA.
THE STRONGEST CLUSTERS ARE CURRENTLY NW OF A SURFACE TROUGH THAT
EXTENDS FROM A 1001 MB LOW OVER HONDURAS NNE TO 20N82W...N OF
19N W OF 82W TO OVER W CUBA. FARTHER E...A MID/UPPER CUT-OFF LOW
IS CENTERED W OF THE LESSER ANTILLES NEAR 14N65W AND IS DRAWING
DRIER AIR S FROM THE CENTRAL/WESTERN ATLC ACROSS THE CENTRAL
CARIBBEAN AND NW VENEZUELA BETWEEN 65W-76W. THIS IS PRODUCING
FAIR CONDITIONS OVER THAT AREA WITH ONLY ISOLATED SHOWERS
DOTTING THE AREA ASSOCIATED WITH THE TROPICAL WAVE.

ATLANTIC...
THE AMPLIFIED UPPER LEVEL RIDGE EXTENDING FROM ACROSS CUBA
WIDENS NE TO BEYOND 32N67W WITH UPPER DIVERGENCE W OF THE AXIS
TO MAINTAIN SCATTERED SHOWERS/ISOLATED THUNDERSTORMS THAT HAVE
PLAGUED FLORIDA FOR THE PAST FEW DAYS. TO THE E...A BROAD DEEP
LAYERED TROUGH SKIRTS THE N BOUNDARY OF THE AREA WITH THE
ATTENDANT COLD FRONT ENTERING THE CENTRAL ATLC NEAR 32N44W
EXTENDING SW ALONG 26N55W THEN W TO 27N65W RETURNING NW AS A
STATIONARY FRONT TO BEYOND 32N71W. SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS ARE WITHIN 90 NM E OF THE FRONT N OF 29N WITH
OVERCAST LOW CLOUDS AND ISOLATED SHOWERS EXTENDING WITHIN 60 NM
SE OF THE REMAINDER OF THE COLD FRONT AND N OF THE FRONTAL
BOUNDARY BEYOND 32N. S OF THE TROUGH/FRONT IS A WEAK MID/UPPER
LEVEL RIDGE THAT SPANS THE ATLC ALONG 24N/25N FROM 40W-65W THEN
GRADUALLY TURNS NE TO BEYOND 32N30W. THIS IS PRODUCING STRONG
SUBSIDENCE/DRY AIR OVER THE AREA FROM 20N-26N...THEN WITH THE
UPPER LOW OVER THE E CARIBBEAN...IS FUNNELING THE SAME AIR INTO
THE CENTRAL CARIBBEAN. OVER THE E ATLC...THE MID/UPPER TROUGH OF
THE PAST FEW DAYS HAS SHORTENED AND DRIFTED S NOW EXTENDING FROM
AN UPPER LOW OVER N MOROCCO NEAR 35N5W TO A SECOND LOW SW OF THE
CANARY ISLANDS NEAR 25N19W TO 22N28W. AT THE SURFACE...THE
SUBTROPICAL RIDGE REMAINS OVER THE E ATLC FROM A WEAKENING 1024
MB HIGH LOCATED NEAR 34N26W SW TO 16N42W. IN THE TROPICAL
ATLC...A RIDGE EXTENDS E/W ALONG 10N/11N FROM OFF THE COAST OF
AFRICA TO 60W. THIS IS KEEPING THE ITCZ AXIS ACTIVE.

$$
WALLACE


WWWW
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