000
AXNT20 KNHC 280542
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST MON NOV 28 2011 

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 10N14W TO 9N17W. THE ITCZ CONTINUES FROM 9N17W ALONG 
5N27W 6N39W TO 6N45W. CLUSTERS OF SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION ARE FROM 3N-10N BETWEEN 16W-42W. 

...DISCUSSION...

GULF OF MEXICO...
A STRONG UPPER TROUGH DIGS S FROM THE GREAT LAKES INTO THE GULF 
OF MEXICO N OF 24N W OF 87W SUPPORTING A COLD FRONT THAT ENTERS 
THE GULF NEAR TALLAHASSEE FLORIDA ALONG 26N86W TO OVER THE E 
YUCATAN PENINSULA AND GUATEMALA. THIS FRONT IS BEGINNING TO 
WEAKEN SLIGHTLY WITH THE GALE FORCE WINDS EXPECTED TO DIMINISH 
BY MORNING. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 
60 NM E OF THE FRONT WITH SCATTERED SHOWERS WITHIN 250 NM W OF 
THE FRONT. DRY STABLE AIR IS MOVING OVER THE NW GULF N OF 24N W 
OF 92W WITH CLEARING SKIES WITHIN 120 NM ALONG THE COAST OF ALL 
OF TEXAS AND MEXICO N OF TAMPICO. A SURFACE RIDGE IS BUILDING W 
OF THE FRONT ANCHORED BY A SERIES OF HIGHS JUST E OF THE ROCKIES 
AND A 1031 MB HIGH OVER N/CENTRAL MEXICO. THE COLD FRONT WILL 
MOVE E OF THE GULF MON EVENING. SURFACE RIDGE WILL CONTINUE TO 
BUILD BEHIND THE FRONT THROUGH THU. A FRONTAL TROUGH MAY MOVE 
INTO THE FAR NW GULF FRI NIGHT. 

CARIBBEAN SEA...
AN UPPER RIDGE DOMINATES THE NW CARIBBEAN W OF 80W WHILE AN 
UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS E CUBA AND 
HISPANIOLA NARROWING ACROSS JAMAICA TO W PANAMA/COSTA RICA. A 
BROAD LOW AMPLITUDE RIDGE COVERS THE REMAINDER OF THE CARIBBEAN 
E OF 70W. DRY STABLE AIR ALOFT AND STRONG SUBSIDENCE ARE NOTED 
ACROSS THE W CARIBBEAN W OF 77W AND THE N/CENTRAL CARIBBEAN N OF 
16N BETWEEN 67W-77W. THE BROAD UPPER RIDGE IS DRAWING TROPICAL 
MOISTURE ACROSS THE SE CARIBBEAN WITH THE MONSOON TROUGH 
EXTENDING FROM COLOMBIA NEAR 11N75W 11N81W TO ACROSS COSTA RICA 
INTO THE E PACIFIC REGION NEAR 10N84W ARE GENERATING SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS S OF 15N TO INLAND OVER COLOMBIA 
AND E PANAMA BETWEEN 69W-77W. A SURFACE TROUGH IS IN THE E 
CARIBBEAN EXTENDING FROM 19N65W ACROSS THE VIRGIN ISLANDS ALONG 
15N66W TO OFF THE COAST OF VENEZUELA NEAR 12N66W WITH SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS E OF THE SURFACE TROUGH TO OVER 
THE LESSER ANTILLES WITH THE STRONGEST ACTIVITY FROM 14N-17N 
BETWEEN 60W-64W. GUADELOUPE HAS REPORTED WELL OVER 2 INCHES OF 
RAIN OVER THE PAST 24 HOURS. THIS IS LEAVING THE REMAINDER OF 
THE CARIBBEAN WITH FAIR WEATHER TONIGHT. HOWEVER...SHOWERS WILL 
BE MOVING INTO THE FAR NW CARIBBEAN OVERNIGHT AS A COLD FRONT 
WILL ENTER THE NW CARIBBEAN REACHING FROM CENTRAL CUBA TO THE SW 
CARIBBEAN TUE WHERE IT WILL STALL AND DISSIPATE THROUGH THU. 
MEANWHILE WEAK SURFACE LOW MAY DEVELOP ALONG THE SURFACE TROUGH 
IN THE E CARIBBEAN MON THROUGH TUE WHERE IT WILL LINGER WED 
THROUGH FRI.

ATLANTIC OCEAN...
A SURFACE RIDGE DOMINATES MOST OF THE W ATLC EXTENDING AN AXIS 
FROM A 1026 MB ABOUT 350 NM N-NW OF BERMUDA THROUGH 32N74W TO 
THE FLORIDA PENINSULA NEAR FORT LAUDERDALE GIVING THE AREA W OF 
65W FAIR WEATHER TONIGHT. AN UPPER TROUGH EXTENDS FROM THE 
CENTRAL ATLC ACROSS THE SW ATLC AND THE S BAHAMA ISLANDS TO OVER 
CUBA/HISPANIOLA AND INTO THE CARIBBEAN SUPPORTING A LINGERING 
SURFACE TROUGH THAT EXTENDS THROUGH 32N53W ALONG 30N56W ALONG 
24N58W TO JUST E OF THE LEEWARD ISLANDS NEAR 18N62W. A BROAD 
HIGH AMPLITUDE UPPER RIDGE COVERS THE CENTRAL ATLC EXTENDING AN 
AXIS FROM AN UPPER HIGH IN THE W TROPICAL ATLC NEAR 11N51W ALONG 
21N46W TO 30N45W PROVIDING DIFFLUENCE ALOFT TO GENERATE 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE 
FROM 10N55W TO E OF THE LESSER ANTILLES NEAR 18N60W...WITHIN 200 
NM OF LINE FROM THE LEEWARD/VIRGIN ISLANDS NEAR 18N63W TO 25N53W 
THEN NARROWING TO WITHIN 125 NM OF LINE FROM 25N54W TO 28N42W. 
FARTHER E IS A WEAKENING 1017 MB LOW CENTERED NEAR 31N39W. THE 
REMAINDER OF THE E ATLC IS DOMINATED BY A BROAD SURFACE RIDGE 
ANCHORED BY A 1030 MB HIGH N OF THE DISCUSSION AREA ABOUT 360 NM 
E OF THE AZORES PROVIDING MOSTLY FAIR WEATHER E OF 34W. A COLD 
FRONT WILL MOVE OFF THE E COAST OF FLORIDA MON NIGHT REACHING 
FROM BERMUDA TO THE SE BAHAMAS LATE WED WHERE IT WILL STALL AND 
WEAKEN INTO A TROUGH. SURFACE RIDGE WILL BUILD IN BEHIND THE 
FRONT AND PREVAIL THROUGH FRI.

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

$$
PAW