000
AXNT20 KNHC 130547
TWDAT 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE MAY 13 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 53W/54W S OF 10N MOVING W 10-15 KT. THE 
WAVE COUPLED WITH THE ITCZ IS ENHANCING CONVECTION OVER THE 
GUIANAS REGION. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION 
IS FROM EQUATOR TO 7N BETWEEN 53W AND 56W. THE GFS MODEL HAS 
LOW-LEVEL MOISTURE FROM THIS TROPICAL WAVE SPREADING OVER 
GUYANA...E VENEZUELA AND THE S WINDWARD ISLANDS ON WED.   

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 8N12W 3N25W 3N48W 4N52W. SCATTERED 
MODERATE CONVECTION IS FROM 1N-4N BETWEEN 16W-19W.  CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120 NM 
N OF AXIS BETWEEN 20W-35W.  SIMILAR CONVECTION IS WITHIN 90 NM 
OF A LINE FROM 5N36W TO 8N46W.

...DISCUSSION...

GULF OF MEXICO...
A STRONG UPPER LEVEL ANTICYCLONIC CIRCULATION IS OFFSHORE OF
THE MID-ATLANTIC STATES MOVING SLOWLY SE ACROSS THE OCEAN. AS OF 
0300 UTC...THE ASSOCIATED COLD FRONT ENTERS THE FORECAST AREA 
NEAR 32N64W THEN CONTINUES ACROSS THE N BAHAMAS AND STRAITS OF 
FLORIDA TURNING STATIONARY NEAR 24N84W EXTENDING ACROSS THE 
CENTRAL GULF TO 25N91W. A VERY FINE LOW LEVEL CLOUD LINE DEFINES 
THE BOUNDARY ACROSS THE E GULF WITH NO PRECIPITATION 
ASSOCIATED WITH FRONT. A 1015 MB SURFACE HIGH PRESSURE IS 
CENTERED NEAR COASTAL MISSISSIPPI AND SETTLING INTO THE E GULF 
PROVIDING A MUCH COOLER AND DRIER AIR MASS. THIS HIGH PRESSURE 
WILL BE SUPPORTED BY A STRENGTHENING UPPER LEVEL RIDGE ANCHORED 
OVER THE GULF OF HONDURAS WITH RIDGE AXIS ALONG 90W KEEPING 
MAINLY NW FLOW ALOFT ACROSS MUCH OF THE GULF OF MEXICO DURING 
THE NEXT 24 HOURS. RETURN SOUTHEASTERLY 15-20 KT SURFACE FLOW IS 
EXPECTED W OF 90W AHEAD OF NEXT DEVELOPING LOW PRESSURE SYSTEM 
OVER W TEXAS WED. 

CARIBBEAN SEA...
A MID TO UPPER LEVEL HIGH CENTERED OVER THE GULF OF HONDURAS 
EXTENDS A RIDGE OVER THE W AND CENTRAL CARIBBEAN WHILE UPPER 
TROUGHING RUNS FROM THE N LEEWARD ISLANDS TO THE N COAST OF 
VENEZUELA. MODERATE TO STRONG SUBSIDENCE/DRY AIR IS EVIDENT 
ACROSS MUCH OF THE CARIBBEAN SEA SUPPRESSING THE DEVELOPMENT OF 
ANY SIGNIFICANT CONVECTION. AT THE SURFACE...HIGH PRESSURE OVER 
THE E ATLC NEAR 27N35W EXTENDS A RIDGE TO THE E CARIBBEAN SEA 
INCLUDING PUERTO RICO AND THE VIRGIN ISLANDS. THIS RIDGE IS 
PROVIDING MOSTLY FAIR WEATHER AND A PREVAILING E-SE SURFACE WIND 
REGIME ACROSS THE N LEEWARD ISLANDS AND PUERTO RICO. ELSEWHERE 
LIGHT TO MODERATE TRADE WINDS OF 10 TO 20 KT ARE ACROSS THE 
CARIBBEAN SEA AS FAIR WEATHER AND CLEAR SKIES DOMINATE THE 
REGION. WITH CURRENT MOVEMENT OF TROPICAL WAVE ACROSS GUYANA AND 
E VENEZUELA TROPICAL MOISTURE WILL INCREASE ACROSS TRINIDAD AND 
TOBAGO AND THE S WINDWARD ISLANDS ON WED.
 
ATLANTIC OCEAN...
A STRONG DEEP-LAYERED CYCLONIC CIRCULATION CENTER IS OFFSHORE OF
THE MID-ATLANTIC STATES NEAR 35N70W. ASSOCIATED COLD FRONT 
ENTERS THE FORECAST AREA NEAR 32N64W THEN CONTINUES ACROSS 
NASSAU BAHAMAS AND THE STRAITS OF FLORIDA. SCATTERED SHOWERS AND 
THUNDERSTORMS ARE WITHIN 90 NM E OF THE FRONT N OF 25N. BEHIND 
FRONT...SURFACE HIGH PRESSURE RIDGE ACROSS THE SE U.S. WILL 
CONTINUE TO BUILD INTO THE W ATLC WATERS ON WED. THE REMAINDER 
OF THE DISCUSSION AREA IS UNDER THE INFLUENCE OF A 1027 MB 
SURFACE HIGH PRESSURE CENTERED NEAR 27N35W. THIS IS PROVIDING 
FAIR WEATHER WITH ONLY PATCHES OF SCATTERED CLOUDINESS ACROSS 
MUCH OF THE CENTRAL AND E ATLC N OF 15N. A BROAD MID TO UPPER 
RIDGE COVERS THE DEEP TROPICS WITH AXIS EXTENDING ALONG 10N. 
THIS UPPER
FEATURE IS AIDING TO ENHANCE CONVECTION ALONG THE ITCZ WEST OF 
32W.

$$
HUFFMAN