000
AXNT20 KNHC 282324
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST FRI NOV 28 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2300 UTC.

...THE ITCZ...
THE ITCZ AXIS IS ANALYZED ALONG 7N10W 4N20W 3N30W 6N40W 8N50W 
AND INTO SOUTH AMERICA NEAR 6N57W. A DISSIPATING SURFACE TROUGH 
IS EMBEDDED WITHIN THE ITCZ AND EXTENDS FROM 13N48W TO 7N49W.  
ELSEWHERE...SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 
FROM 2N-6N BETWEEN 20W-31W. A SIMILAR CLUSTER OF MODERATE 
CONVECTION IS FROM 6N-8N BETWEEN 32W-35W.

...DISCUSSION...

GULF OF MEXICO...
AS OF 2100 UTC...A SFC RIDGE SURROUNDS A 1017 MB HIGH CENTERED 
JUST WEST OF THE BAHAMAS AND EXTENDS ACROSS THE FLORIDA 
PENINSULA INTO THE CENTRAL AND EAST GULF. THIS SURFACE FEATURE 
CONTINUES TO PRODUCE MOSTLY FAIR WEATHER AND CLEAR SKIES ACROSS 
THE REGION THIS EVENING. A FRONTAL BOUNDARY STRETCHING ACROSS 
THE SOUTHERN CONUS IS PUSHING SCATTERED SHOWERS AND ISOLATED 
THUNDERSTORMS INTO THE FAR NORTHERN GULF WATERS. THE FRONT IS 
EXPECTED TO ENTER THE GULF TOMORROW MORNING. LIGHT TO MODERATE 
SOUTHERLY RETURN FLOW AROUND THE AFOREMENTIONED SFC HIGH WILL 
INCREASE TO NEAR GALE FORCE IN THE NW GULF IN ADVANCE OF THE 
FRONT. A RELATIVELY COOLER AND DRIER AIR MASS WILL INVADE THE 
GULF WITH N TO NW SURFACE WINDS IN THE WAKE OF THE FRONTAL 
PASSAGE. 

CARIBBEAN SEA...
A STATIONARY 1011 MB SFC LOW REMAINS SITUATED OVER 
PANAMA...GENERATING SCATTERED SHOWERS ACROSS THE SW CARIBBEAN S 
OF 11N. PATCHES OF LOW LEVEL MOISTURE EMBEDDED IN THE TRADE WIND 
FLOW ARE NOTED ACROSS THE REMAINDER OF THE BASIN WITH A MORE 
CONCENTRATED CLUSTER JUST SOUTH OF HISPANIOLA. TRADE WINDS WILL 
WEAKEN ACROSS THE CENTRAL AND EAST CARIBBEAN AS A HIGH PRESSURE 
RIDGE OVER THE W ATLC SHIFTS EAST. WINDS IN THE NW CARIBBEAN 
WILL INCREASE OVER THE NEXT 24-48 HOURS IN ADVANCE OF A GULF OF 
MEXICO COLD FRONT. ALOFT...STRONG SUBSIDENCE AROUND AN UPPER 
HIGH OVER NICARAGUA CONTINUES TO INHIBIT THE DEVELOPMENT OF 
SIGNIFICANT CONVECTION.

ATLANTIC OCEAN...
AS OF 2100 UTC...A 1017 MB SFC HIGH JUST SOUTH OF GRAND BAHAMA 
ISLAND EXTENDS A RIDGE ACROSS THE W ATLC...MAINTAINING TRANQUIL 
CONDITIONS. A SFC TROUGH...REMNANTS OF A COLD FRONT...STRETCHES 
FROM 31N54W ALONG 25N60W TO 22N67W. SCATTERED MODERATE 
CONVECTION IS WITHIN 150 NM AHEAD OF THE TROUGH NORTH OF 24N.
A STRONG 1000 MB SFC LOW CONTINUES TO SPIN OVER THE CENTRAL ATLC 
NEAR 33N39W.  THIS LOW IS ACCOMPANIED BY SHOWERS AND 
SQUALLS...AND THE CLOUD PATTERN IS EXHIBITING SOME 
SUBTROPICAL-LIKE CHARACTERISTICS. A SFC TROUGH EXTENDS FROM THE 
LOW CENTER ALONG 32N35W TO 28N26W. SCATTERED SHOWERS ARE WITHIN 
120 NM EITHER SIDE OF THE TROUGH. THIS LOW PRESSURE SYSTEM IS 
MOVING NORTHWARD OVER COOLER WATERS AND IS EXPECTED TO MERGE 
WITH A FRONTAL SYSTEM OVER THE NEXT 24 HOURS. FURTHER 
SOUTH...ANOTHER SFC TROUGH...REMNANTS OF A COLD FRONT...EXTENDS 
FROM 18N43W ALONG 13N50W TO THE COAST OF VENEZUELA NEAR 9N60W. 
SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS ARE 
WITHIN 140 NM EITHER SIDE OF THE BOUNDARY. THE E ATLC REMAINS 
UNDER THE INFLUENCE OF A SURFACE RIDGE CENTERED WELL N OF THE 
DISCUSSION AREA. ALOFT...DIVERGENCE AROUND AN UPPER HIGH NEAR 
8N35W IS ENHANCING CONVECTION ALONG THE ITCZ.
 
$$
RJW