000
AXNT20 KNHC 080537
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST SAT JAN 08 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND 
RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...ITCZ...

THE ITCZ AXIS IS ANALYZED FROM NRN LIBERIA NEAR 6N11W ALONG 
3N26W 2N40W EQ49W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION 
IS FROM 3N-5N BETWEEN 21W-26W. SIMILAR ACTIVITY IS FROM EQ-6N 
BETWEEN 40W-50W. 

...DISCUSSION...

GULF OF MEXICO...
SURFACE RIDGING AROUND A 1012 MB HIGH N OF THE YUCATAN PENINSULA 
NEAR 23N90W CONTINUES TO PROVIDE GENERALLY FAIR WEATHER ACROSS 
THE GULF OF MEXICO TONIGHT. ANTI-CYCLONIC SURFACE WINDS OF 15-20 
KTS ARE AROUND THE RIDGE WITH SOME 25 KT WLY WINDS NOTED IN THE 
NE PORTION OF THE BASIN. THE SURFACE RIDGE IS SUPPORTED BY AN 
UPPER LEVEL RIDGE EXTENDING UP THE THE ERN COAST OF MEXICO AND 
ACROSS CENTRAL TEXAS PROVIDING NELY FLOW ALOFT ACROSS THE GULF. 
EXPECT A REINFORCING COLD FRONT TO MOVE INTO THE NE GULF WITHIN 
THE NEXT 6-12 HOURS AND EXITING THE GULF REGION WITHIN 24 HOURS. 
SWLY RETURN FLOW IS EXPECTED TO INCREASE ACROSS THE NW GULF AS A 
LOW PRESSURE SYSTEM FORMS ALONG THE COASTLINE EARLY SUNDAY WITH 
SHOWER ACTIVITY EXPECTED.  

CARIBBEAN SEA...
AS OF 0300 UTC...A WEAK COLD FRONT EXTENDS ACROSS THE WINDWARD 
PASSAGE TO N OF JAMAICA NEAR 19N77W WHERE IT CONTINUES AS A 
DISSIPATING COLD FRONT INTO HONDURAS NEAR 16N85W. POSSIBLE 
ISOLATED SHOWERS ARE WITHIN 30 NM OF THE AXIS. THE FRONT IS 
SUPPORTED BY AN UPPER LEVEL TROUGH THAT EXTENDS FROM THE GREAT 
LAKES REGION OUT ACROSS THE WRN ATLC CONTINUING INTO THE NW 
CARIBBEAN. HOWEVER...THE TROUGH IS ACCOMPANIED BY MAINLY DRY AIR 
INDICATED BY WATER VAPOR IMAGERY...WHICH IS PROVIDING FAIR 
CONDITIONS ACROSS THE REMAINDER OF THE BASIN. A FEW SHOWERS ARE 
NOTED ACROSS NRN HISPANIOLA AND OFF THE COAST OF COSTA RICA. IN 
THE UPPER LEVELS...SWLY FLOW ALOFT COVERS THE AREA E OF 80W 
AROUND AN UPPER LEVEL RIDGE CENTERED N ERN BRAZIL. SOME PATCHES 
OF MOISTURE EMBEDDED IN THIS SWLY FLOW ARE SUPPORTING AREAS OF 
UPPER LEVEL CLOUDS. EXPECT...THE FRONT TO CONTINUE DISSIPATING 
AS MODERATE TO FRESH TRADEWINDS CONTINUE ACROSS THE ERN HALF OF 
THE BASIN.   

ATLANTIC OCEAN...
AS OF 0300 UTC...A COLD FRONT ENTERS THE DISCUSSION AREA NEAR 
32N57W CONTINUING SW ALONG 25N64W 20N74W AND INTO THE CARIBBEAN. 
SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 30 NM EITHER SIDE OF 
THE AXIS FROM 24N-27N. SIMILAR ACTIVITY IS ALSO FARTHER AHEAD OF 
THE FRONT WITHIN 120 NM AND 240 NM. THIS ACTIVITY IS ASSOCIATED 
WITH DIFFLUENT FLOW ALOFT BETWEEN A LONGWAVE UPPER LEVEL TROUGH 
EXTENDING FROM THE GREAT LAKES REGION TO NEAR 30N70W CONTINUING 
DOWN 70W WHICH SUPPORTS THE COLD FRONT...AND AN UPPER LEVEL 
RIDGE TO THE E EXTENDING FROM N OF ERN BRAZIL NEAR 2N45W TO NEAR 
19N54W TO 42N41W. A REINFORCING COLD FRONT IS EXPECTED TO FORM 
BEHIND THE FRONT OVER THE NEXT 24 HRS WITH GALE FORCE WINDS 
EXPECTED N OF 30N W OF 80W WITHIN THE NEXT 12 HOURS. THE 
REMAINDER OF THE BASIN IS DOMINATED BY A BROAD SURFACE RIDGE 
ANCHORED BY A 1024 MB HIGH NEAR 30N34W PROVIDING MOSTLY FAIR 
WEATHER ACROSS THE ERN ATLC. ALOFT...AN UPPER LEVEL TROUGH 
EXTENDS FROM W OF PORTUGAL ACROSS THE CANARY AND CAPE VERDE 
ISLANDS SUPPORTING A FRONTAL SYSTEM N OF THE DISCUSSION AREA. 

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

$$
WALTON