000
AXNT20 KNHC 291147
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST MON DEC 29 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.

...THE ITCZ...

ITCZ IS CENTERED ALONG 06N10W TO 04N25W TO 09N43W TO 04N51W. 
SCATTERED MODERATE CONVECTION WITHIN 120 NM EITHER SIDE OF AXIS 
BETWEEN 21W AND 30W. SCATTERED MODERATE ISOLATED STRONG WITHIN 
120 NM N OF AXIS BETWEEN 33W AND 40W. 

...DISCUSSION...

GULF OF MEXICO...
A WEAK STATIONARY FRONT EXTENDS FROM THE FLORIDA PANHANDLE NEAR 
FORT WALTON BEACH TO 25N95W TO 20N96W NEAR VERACRUZ MEXICO. BUOY 
OBSERVATIONS AND AN ASCAT PASS FROM 0300Z SHOWED N TO NE WINDS 
AROUND 15 TO 20 KT TO THE NORTH OF FRONT. GENERALLY LIGHT TO 
MODERATE E TO SE WINDS ARE EVIDENT SOUTH OF THE FRONT. 
CONVECTION HAD BEEN FLARING ALONG THE FRONT SW OF THE MOUTH OF 
MISSISSIPPI...BUT THIS HAS DISSIPATED OVER THE PAST SEVERAL 
HOURS. NO SIGNIFICANT CONVECTION IS NOTED ANYWHERE THROUGHOUT 
THE GULF. UPPER SUPPORT IN THE FORM OF AN UPPER TROUGH OVER THE 
MID MISSISSIPPI VALLEY PROGRESSES INTO THE CAROLINAS BY 
TONIGHT...RESULTING IN THE SOUTHERN PORTIONS OF THE FRONT 
DISSIPATING. WINDS DIMINISH AS 1027 MB HIGH PRES CENTERED OVER E 
TEXAS MOVES THROUGH THE DEEP SOUTH TUE. WINDS INCREASE OVER 
NORTHERN WATERS BY WED...AS ANOTHER UPPER TROUGH MOVES FROM THE 
GREAT LAKES THROUGH THE MID-ATLANTIC STATES ALLOWING A WEAK COLD 
FRONT TO ENTER THE GULF BY LATE TUE.

CARIBBEAN SEA...
MAIN ISSUE IS PERSISTENT STRONG TRADE WIND FLOW SOUTH OF HIGH 
PRES NE OF THE BAHAMAS. AN ASCAT PASS FROM 0300Z SHOWED WINDS TO 
25 KT OFF THE COLOMBIAN COAST. BUOYS AND SSMI DATA SHOW 
GENERALLY 15 TO 20 KT FLOW CONTINUING ACROSS ALL BUT THE FAR NW 
CARIBBEAN WATERS. THESE WINDS ARE EXPECTED TO DIMINISH THROUGH 
THROUGH MIDWEEK AS THE HIGH PRES WEAKENS AND SHIFTS EAST AHEAD 
OF A TROUGH DIGGING OFF THE EAST COAST. DEEP LAYER MOISTURE IS 
LACKING ACROSS THE BASIN...NO SIGNIFICANT WEATHER IS NOTED.

ATLANTIC OCEAN...
UPPER TROUGH FROM CLOSED LOW W OF AZORES NEAR 39N35W TO 24N42W 
TO THE LEEWARD ISLANDS IS DIGGING EAST AHEAD OF A MID/UPPER 
RIDGE BUILDING OVER BAHAMAS. ASSOCIATED SURFACE TROUGH EXTENDS 
FROM 32N29N TO 21N37W. A RELATED BUT DETACHED INVERTED TROUGH 
FURTHER SOUTH FROM 15N39W TO THE ITCZ NEAR 09N44W. DIVERGENT SW 
FLOW ALOFT BETWEEN THE UPPER TROUGH AND AN UPPER ANTICYCLONE 
OVER THE GUINEA COAST ARE PERPETUATING A BROAD BAND OF MOISTURE 
FROM GUYANA TO MAURITANIA...AND ENHANCING EMBEDDED MODERATE 
CONVECTION NEAR THE ITCZ AS DESCRIBED ABOVE. QUIKSCAT AND SSMI 
DATA SHOW A BROAD AREA OF STRONG NW WINDS TO 30 KT W OF THE 
TROUGH...WITH 20 TO 25 KT SE WINDS E OF THE TROUGH NEAR THE 
CANARY ISLANDS. FURTHER WEST...HIGH PRES DOMINATES THE AREA NE 
OF THE BAHAMAS UNDER THE BUILDING RIDGE. THIS IS MAINTAINING 
FRESH TO STRONG TRADES INTO THE WINDWARD ISLANDS...BUT KEEPING 
GENERALLY LIGHT FLOW OVER BETWEEN BERMUDA AND THE BAHAMAS. A 
COLD FRONT WILL MOVE OFF THE SOUTHEAST U.S. COAST LATE 
TODAY...REACHING A POSITION E OF BERMUDA BY TUE BEFORE 
DISSIPATING WED. A SECOND COLD FRONT MOVES OFF THE COAST BY LATE 
WED.

$$
CHRISTENSEN