000
AXNT20 KNHC 111136
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SAT FEB 11 2012

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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL 
ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL 
ATLC NEAR 10N14W TO 3N23W WHERE THE ITCZ CONTINUES S CROSSING 
THE EQUATOR NEAR 31W INTO SOUTH AMERICA NEAR 2S45W. CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM THE  
MONSOON TROUGH/ITCZ TO S OF THE EQUATOR BETWEEN 20W-30W. 
CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 6N TO JUST OF 
OF THE EQUATOR BETWEEN 8W-20W. 

...DISCUSSION...

GULF OF MEXICO...
AN UPPER TROUGH IS ACROSS THE E CONUS AND N GULF EXTENDING INTO 
THE W ATLC MOVING RAPIDLY AND SUPPORTING A FAST MOVING COLD 
FRONT THAT AT 11/0900 UTC ENTERS THE GULF ACROSS FLORIDA BETWEEN 
VERO BEACH TO NAPLES ALONG 23N87W TO TUXPAN MEXICO. SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 75 NM SE 
OF THE FRONT E OF 86W WITH ISOLATED SHOWERS WITHIN 75 NM NE OF 
THE FRONT E OF 90W. SCATTERED TO HEAVY SHOWERS ARE OVER THE SW 
GULF S OF 26N TO THE FRONT W OF 90W. THE REINFORCING COLD FRONT 
OVER LOUISIANA IS BEGINNING TO DISSIPATE AND IS NOT EXPECTED TO 
ENTER THE GULF WATERS. A BROAD UPPER RIDGE DOMINATES THE 
REMAINDER OF THE GULF AND IS DRAWING TROPICAL MOISTURE ALOFT 
ACROSS THE SE GULF ENHANCING THE ACTIVITY ABOVE. THE COLD FRONT 
WILL MOVE OUT OF THE GULF THIS AFTERNOON. SOUTHERLY RETURN FLOW 
WILL SET UP OVER THE NW GULF SUN NIGHT AND SPREAD E ACROSS THE 
ENTIRE GULF BY LATE MON. THE NEXT COLD FRONT WILL MOVE E ACROSS 
THE NW COASTAL PLAIN MON NIGHT STALLING OVER THE FLORIDA 
PANHANDLE TUE NIGHT. REMNANTS OF THE FRONT WILL THEN LIFT N WED 
AS A RIDGE BUILDS FROM TAMPA BAY TO THE TEXAS COASTAL BEND. 

CARIBBEAN SEA...
BROAD UPPER RIDGE CONTINUES TO DOMINATE THE CARIBBEAN WITH THE 
PRIMARY AXIS ALONG 75W AND EXTENDING OVER THE S GULF OF MEXICO 
AND INTO THE W ATLC. THE PRESSURE GRADIENT CONTINUES TO MAINTAIN 
FRESH NE TO E TRADE WINDS ACROSS THE BASIN. THE TRADE WINDS ARE 
USHERING IN SOME LOW LEVEL MOISTURE WITH POSSIBLE ISOLATED 
SHOWERS ARE OVER THE SE CARIBBEAN S OF 15N W OF 65W TO THE 
WINDWARD ISLANDS. THE REMAINDER OF THE CARIBBEAN IS UNDER MOSTLY 
CLEAR SKIES AGAIN THIS MORNING. THE GULF OF MEXICO COLD FRONT 
WILL MOVE INTO THE NW CARIBBEAN TODAY THEN STALL AND DISSIPATE 
OVER THE CARIBBEAN FROM HISPANIOLA TO HONDURAS MON AND TUE. 

ATLANTIC OCEAN...
THE UPPER TROUGH OVER THE E CONUS AND N GULF OF MEXICO HAS MOVED 
INTO THE W ATLC AND SUPPORTING A FAST MOVING COLD FRONT THAT AT 
11/0900 UTC EXTENDS FROM A 1006 MB LOW N OF THE DISCUSSION AREA 
THROUGH 32N76W ACROSS FLORIDA INTO THE GULF OF MEXICO NEAR VERO 
BEACH. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 30N75W ACROSS 
GRAND BAHAMA ISLANDS TO 24N81W IN THE STRAITS OF FLORIDA. A 
SHORTWAVE UPPER TROUGH EXTENDS FROM NEAR CHARLESTON SOUTH 
CAROLINA TO OVER THE NE FLORIDA PENINSULA TO NEAR ORLANDO 
FLORIDA SUPPORTING SURFACE TROUGH THAT AT 11/0900 UTC EXTENDS 
FROM 32N79W TO OVER DAYTONA BEACH FLORIDA TO JUST S OF TAMPA 
FLORIDA. SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 120 NM SE OF 
THE LEADING SURFACE TROUGH S OF 28N WITH SCATTERED SHOWERS AND 
POSSIBLE ISOLATED THUNDERSTORMS OVER THE REMAINDER OF THE AREA W 
OF A LINE FROM 23N78W ALONG 28N71W TO BEYOND BERMUDA AND E OF 
THE TRAILING SURFACE TROUGH. THE BROAD UPPER RIDGE OVER THE 
CARIBBEAN EXTENDS OVER THE REMAINDER OF THE W ATLC WITH A RIDGE 
AXIS EXTENDING FROM THE MONA PASSAGE NE TO BEYOND 32N55W. AN 
UPPER TROUGH IS N OF THE DISCUSSION DRAPING A DISSIPATING COLD 
FRONT INTO THE W/CENTRAL ATLC NEAR 32N54W TO 29N61W WHERE IT 
BECOMES A DISSIPATING STATIONARY FRONT TO 29N72W. ISOLATED 
SHOWERS ARE N OF 28N BETWEEN 45W AND THE FRONTAL BOUNDARY. A 
BROAD UPPER TROUGH DOMINATES THE REMAINDER OF THE ATLC WITH THE 
AXIS EXTENDING THROUGH 32N21W SW ALONG 21N37W INTO THE TROPICS 
TO 8N50W. A BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF THE 
ATLC ANCHORED BY A 1026 MB HIGH JUST S OF THE AZORES AND A RIDGE 
AXIS EXTENDING THROUGH 32N38W TO 24N71W LEAVING THE REMAINDER OF 
THE ATLC WATERS UNDER FAIR WEATHER CONDITIONS THIS MORNING. W 
ATLC COLD FRONT WILL EXTEND FROM 32N69W TO THE FLORIDA STRAITS 
LATER TODAY. A REINFORCING FRONT WILL MOVE THROUGH N WATERS 
TONIGHT AND CATCH UP WITH THE ABOVE FRONT FROM 32N70W TO THE 
WINDWARD PASSAGE ON SUN BEFORE MOVING INTO THE CENTRAL ATLC ON 
MON. SOUTHERLY RETURN FLOW SETS UP OVER THE NW GULF TUE AND WED.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
PAW