[Tropical] Tropical Weather Discussion

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AXNT20 KNHC 070534
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE JUN 07 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...

TROPICAL WAVE IN THE FAR EASTERN ATLANTIC OCEAN IS ALONG 21W
SOUTH OF 14N MOVING WEST AT AN ESTIMATED SPEED OF 10 KT. THE
WAVE STRUCTURE CONTINUES TO BE COMPLEX WITH A LARGE CYCLONIC
ENVELOPE.  HOWEVER...THERE IS NO SIGNIFICANT CONVECTION AT THIS
TIME.

CENTRAL ATLANTIC OCEAN TROPICAL WAVE IS ALONG 53W SOUTH OF 16N
MOVING WEST 10-15 KT.  THERE IS LITTLE OR NO SATELLITE SIGNATURE
AND THE CURRENT POSITION IS BASED PRIMARILY ON EXTRAPOLATION.
AND THE 0000 UTC CAYENNE SOUNDING WHICH DID NOT INDICATE WAVE
PASSAGE.  NO SIGNIFICANT CONVECTION IS NOTED.

CARIBBEAN SEA TROPICAL WAVE IS ALONG 74W SOUTH OF 20N MOVING WEST
10-15 KT. THE WAVE CONTINUES TO INTERACT WITH A MIDDLE TO UPPER
LEVEL LOW OVER HAITI.  WHILE PRODUCING A SIGNIFICANT AMOUNT OF
CLOUDINESS AND SHOWERS/TSTMS OVER THE E CARIBBEAN...THE UPPER
LOW IS MASKING THE SATELLITE SIGNATURE OF THE WAVE ITSELF.  AS
SUCH...THE WAVE POSITION IS BASED ON EXTRAPOLATION USING AN
AVERAGE SPEED OF 4-5 DEG/DAY.

TROPICAL WAVE OVER GUATEMALA AND S MEXICO ALONG 92W SOUTH OF 17N
MOVING WEST 10-15 KT. THE WAVE IS EMBEDDED WITHIN A BROAD
MONSOON-TYPE CIRCULATION OVER THE E PACIFIC OCEAN AND CENTRAL
AMERICA. THIS OVERALL PATTERN HAS BEEN PRODUCING AN ACTIVE
CONVECTIVE PATTERN OVER ALL OF CENTRAL AMERICA AND THIS SHOULD
CONTINUE FOR THE NEXT FEW DAYS AS THE WAVE SLOWS DOWN WITHIN THE
LARGER SCALE CIRCULATION AND TROPICAL MOISTURE POOLS OVER THE
AREA.

...THE ITCZ...

ITCZ IS CENTERED ALONG 12N10W 7N40W 8N60W...THEN ACROSS N
VENEZUELA AND COLOMBIA.  SCATTERED MODERATE/ISOLATED STRONG
CONVECTION FROM 5N-9N BETWEEN 27W-47W.

.DISCUSSION...

GULF OF MEXICO...
A MID TO UPPER LEVEL TROUGH HAS ONCE AGAIN BECOME ESTABLISHED
OVER THE CENTRAL GLFMEX AND WILL BE A KEY PLAYER IN THE WEATHER
OVER THE NEXT 2 DAYS AS IT REMAINS ESSENTIALLY STATIONARY ALONG
90W. IN A PATTERN REMINISCENT TO LAST WEEK...DEEP-LAYERED SLY
FLOW TO THE EAST OF THE TROUGH WILL ALLOW A PLUME OF MOISTURE TO
EXTEND NWD FROM THE W CARIBBEAN.  WATER VAPOR IMAGERY ALREADY
SHOWS MOISTURE OVERSPREADING FLORIDA FROM S TO N AND THE 0000
UTC SOUNDINGS FROM MIAMI AND KEY WEST SHOW PWAT AGAIN NEAR 2
INCHES.  MOISTURE VALUES SHOULD CONTINUE TO INCREASE THROUGH THE
NEXT 24 WHILE AT THE SAME TIME THE UPPER LEVEL FLOW BECOMES
INCREASINGLY DIVERGENT AS THE TROUGH SHARPENS AND A CLOSED LOW
FORMS LATER TODAY.  BOTTOM LINE...UNSETTLED/WET WEATHER WILL
LIKELY CONTINUE FOR FLORIDA THROUGH AT LEAST MID-WEEK.  ACTIVITY
SHOULD BE PRIMARILY FOCUSED DURING THE AFTERNOON HOURS
TODAY...BUT MAY BECOME MORE NOCTURNAL IN NATURE BY MID-WEEK AS A
CLOSED UPPER LOW FORMS LATE TUE. OVER THE W GLFMEX...THE
ESTABLISHED UPPER TROF IS PRODUCING SUBSIDENCE AND DRY/STABLE
CONDITIONS ALOFT W OF 90W WHICH IS EXPECTED TO PREVAIL FOR
SEVERAL MORE DAYS RESULTING IN RATHER TRANQUIL WEATHER.  THE ONE
CAVEAT...ACTIVITY OVER THE S UNITED STATES MAY CLIP THE N GULF
COAST AS IS CURRENTLY THE CASE ALONG LOUISIANA.

CARIBBEAN...
A RATHER ACTIVE PATTERN CONTINUES OVER THE CARIBBEAN WITH TWO
IMPRESSIVE AREAS OF CONVECTION.  OVER THE W CARIBBEAN...A LARGE
MONSOON-TYPE CIRCULATION CONTINUES OVER THE E PACIFIC AND
CENTRAL AMERICA ALLOWING MOISTURE TO POOL ACROSS THE AREA.  AS A
RESULT...A LARGE AREA OF WIDESPREAD CLOUDINESS AND WIDELY
SCATTERED SHOWERS AND STRONG TSTMS COVER ALL OF CENTRAL AMERICA
AND PORTIONS OF S MEXICO.  THIS ACTIVITY WILL LIKELY BE ENHANCED
DURING THE NEXT COUPLE OF DAYS MOISTURE FROM A TROPICAL WAVE
POOLS OVER THE AREA AND UPPER LEVEL DIVERGENCE INCREASES AHEAD
OF A TROUGH DEVELOPING OVER THE CENTRAL GLFMEX.  BOTTOM
LINE...EXPECT SEVERAL MORE DAYS OF UNSETTLED/WET WEATHER OVER
THE NW CARIBBEAN AND CENTRAL AMERICA. THE SECOND AREA OF
INTEREST IS LOCATED OVER THE E CARIBBEAN WHERE A WELL-DEFINED
UPPER LOW OVER HAITI IS INTERACTING WITH A TROPICAL WAVE ALONG
74W.  THIS INTERACTION IS PRODUCING A LARGE AREA OF CLOUDINESS
AND SCATTERED SHOWERS/TSTMS OVER A GOOD PORTION OF THE CENTRAL
TO E CARIBBEAN.  THE STRONGEST OF THIS ACTIVITY IS LOCATED OVER
THE S CARIBBEAN GENERALLY S OF 15N BETWEEN 62W-74W INCLUDING THE
ABC ISLANDS.  HOWEVER...AS THE UPPER LOW BEGINS TO MOVE SLOWLY
NW TOWARD THE S BAHAMAS OR TURKS/CAICOS TONIGHT...DEEP-LAYERED
TROPICAL MOISTURE WILL GET PULLED NWD.  THIS SETUP WILL SUPPORT
SEVERAL DAYS OF ACTIVE CONVECTION OVER THE E CARIBBEAN WITH
INCREASING COVERAGE N OF 15N TUE AND WED.

ATLANTIC...
THE AMPLIFIED UPPER LEVEL RIDGE PATTERN OVER THE W ATLC WATERS
HAS FLATTENED DURING THE LAST 24 HOURS COURTESY OF A SHORTWAVE
TROUGH DROPPING SEWD OVER BERMUDA. HOWEVER...THE RIDGE SHOULD
RE-AMPLIFY OVER THE NEXT COUPLE OF DAYS AS A TROUGH SHARPENS
OVER THE GLFMEX.  THIS WOULD TEND TO PRODUCE DEEP-LAYERED
MOISTURE ADVECTION FROM THE W CARIBBEAN OVER CUBA AND N BAHAMAS
SUPPORTING ENHANCED CLOUDINESS AND POSSIBLE SHOWERS/TSTMS OVER
THE W ATLC DURING THE NEXT FEW DAYS.  THE S BAHAMAS AND
TURKS/CAICOS MAY ESCAPE THIS MOISTURE SURGE AS AN UPPER LOW OVER
HAITI MOVES NWD PRODUCING CONFLUENT FLOW AND SOME DRYING AIR
ALOFT.  AT THE SURFACE...THE W EXTENT OF THE SUBTROPICAL RIDGE
HAS BEEN WEAKENED BY A WEAK FRONTAL BOUNDARY MOVING INTO THE
AREA ALONG 32N55W TO 25N65W. THE FRONT LACKS APPRECIABLE UPPER
SUPPORT BUT IS ACCOMPANIED BY SCATTERED TO BROKEN CLOUDINESS AND
WIDELY SCATTERED SHOWERS WITHIN 125 NM EITHER SIDE OF BOUNDARY E
OF 62W.  FURTHER S...A REMNANT FRONTAL TROUGH REMAINS TRAPPED
BENEATH THE SUBTROPICAL RIDGE ALONG 29N45W 23N50W 21N60W TO
23N71W.  SCATTERED SHOWERS AND ISOLATED TSTMS ARE NOTED WITHIN
60 NM EITHER SIDE OF BOUNDARY ESPECIALLY E OF 55W. SATELLITE
IMAGERY INDICATES THE W PORTION OF THE FRONTAL TROUGH HAS
FRACTURED FORMING A SCREAMING EAGLE TYPE FEATURE APPROXIMATELY
100-200 NM NE OF THE TURKS/CAICOS.  THIS FEATURE WILL LIKELY
MOVE WESTWARD DURING THE NEXT DAY OR SO WITH A SMALL AREA OF
SCATTERED SHALLOW TOPPED SHOWERS AFFECTING THE S TO CENTRAL
BAHAMAS TODAY AND WED. OVER THE CENTRAL ATLC...A SHORTWAVE
TROUGH IS OBSERVED DROPPING QUICKLY SEWD ALONG 42W AND PRODUCING
SOME HIGH CLOUDINESS AND PERHAPS A FEW SHOWERS WITHIN 240 NM TO
THE E MAINLY N OF 22N.  THIS SHORTWAVE TROUGH WILL ACT TO
AMPLIFY/REINFORCE AN EXISTING LARGER SCALE TROUGH EXTENDING
ACROSS THE CENTRAL TO E ATLC FROM 30N25W SWD INTO THE DEEP
TROPICAL ATLC NEAR 10N50W.  THIS SAME TROUGH IS ALSO WEAKENING
THE W EXTENT...W OF 40W...OF THE UPPER RIDGE OVER THE DEEP
TROPICAL ATLC ALONG.  THE RIDGE REMAINS WELL-DEFINED ELSEWHERE E
OF 40W.

$$
RHOME


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