000
AXNT20 KNHC 121149
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST SAT FEB 12 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...ITCZ...

THE ITCZ IS ANALYZED FROM LIBERIA NEAR 6N10W 2N20W 1N40W 
CROSSING THE EQUATOR INTO SOUTH AMERICA NEAR 49W. CLUSTERS OF 
SCATTERED MODERATE TO STRONG CONVECTION ARE S OF 4N W OF 36W 
ACROSS THE EQUATOR AND INTO SOUTH AMERICA. CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75 NM OF LINE 
FROM THE COAST OF SERRA LEONE AFRICA NEAR 7N12W TO THE EQUATOR 
NEAR 26W AND FROM 4N-6N BETWEEN 44W-49W.   

...DISCUSSION...

GULF OF MEXICO...
A BROAD FLAT UPPER TROUGH COVERS THE E CONUS/GULF OF MEXICO INTO 
THE W ATLC GIVING THE GULF SW FLOW ALOFT SUPPORTING A COLD FRONT 
IN THE W ATLC AND CARIBBEAN. DENSE LOW LEVEL CLOUDS WITH 
SCATTERED SHOWERS REMAIN OVER THE GULF S OF LINE FROM FLORIDA 
JUST S OF TAMPA ALONG 23N94W TO BROWNSVILLE TEXAS BANKING ALONG 
THE THE SIERRA MADRE MOUNTAINS IN MEXICO AND OVER THE YUCATAN 
PENINSULA. A SURFACE RIDGE CONTINUES TO DOMINATE THE GULF 
ANCHORED AT 12/0900 UTC BY A 1032 MB HIGH OVER S TEXAS. HIGH 
PRESSURE WILL REMAIN IN CONTROL OF THE GULF THROUGH THE WEEKEND 
INTO THE FIRST OF NEXT WEEK.

CARIBBEAN SEA...
AS OF 12/0900 UTC...A COLD FRONT EXTENDS FROM THE W ATLC ACROSS 
CUBA NEAR SAGUA LA GRANDE TO THE YUCATAN PENINSULA NEAR 21N87W 
WHERE IT BECOMES STATIONARY S ALONG THE COAST OF BELIZE TO THE 
COAST OF GUATEMALA. DENSE LOW LEVEL CLOUDS WITH SCATTERED 
SHOWERS REMAIN W OF THE FRONT INTO THE GULF OF MEXICO AND 
ISOLATED SHOWERS ARE WITHIN 60 NM S OF THE COLD FRONT AND E OF 
THE STATIONARY FRONT. AN UPPER RIDGE COVERS THE W CARIBBEAN 
WHILE A SECOND UPPER RIDGE COVERS THE E CARIBBEAN INDUCING AN 
UPPER TROUGH THAT EXTENDS FROM THE WINDWARD PASSAGE TO THE 
PANAMA/COSTA RICA BORDER. HOWEVER...STRONG SUBSIDENCE AND DRY 
STABLE AIR COVERS THE ENTIRE BASIN LIMITING DEEP LAYERED SHOWER 
ACTIVITY. FRESH TO STRONG EASTERLY TRADE WINDS ARE ACROSS THE E 
CARIBBEAN USHERING IN SOME LOW LEVEL FAST MOVING ISOLATED 
SHOWERS MAINLY FROM 14N-20N BETWEEN 66W-74W INCLUDING PORTIONS 
OF PUERTO RICO AND HISPANIOLA. TRADE WINDS ARE EXPECTED TO 
DIMINISH SLIGHTLY LATER TODAY AS THE FRONT WILL EXTEND FROM E 
CUBA TO NE HONDURAS BY TONIGHT THEN STALL AND DISSIPATE LATE SUN.

ATLANTIC OCEAN...
A BROAD FLAT UPPER TROUGH COVERS THE W ATLC W OF 70W TO OVER THE 
E CONUS AND GULF OF MEXICO SUPPORTING A COLD FRONT THAT AT 
12/0900 UTC EXTENDS INTO THE W ATLC THROUGH 32N68W ACROSS THE 
BAHAMAS NEAR 24N77W TO OVER CUBA NEAR SAGUA LA GRANDE INTO THE 
CARIBBEAN. SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE 
WITHIN 45/60 NM E OF THE FRONT N OF 26N WITH DENSE LOW LEVEL 
CLOUDS AND SCATTERED SHOWERS S OF 27N WITHIN 150 NM W OF THE 
FRONT TO THE BAHAMAS THEN WITHIN 225 NM W OF THE FRONT ACROSS 
THE FLORIDA PENINSULA AND THROUGH THE STRAITS OF FLORIDA. A VERY 
BROAD UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC ACROSS THE 
CENTRAL INTO THE E ATLC ANCHORED NEAR 26N46W. A SURFACE RIDGE 
COVERS THE E AND CENTRAL ATLC ANCHORED BY A 1030 MB HIGH SSW OF 
THE AZORES NEAR 32N31W AND A 1029 MB HIGH NEAR 28N38W WITH THE 
RIDGE AXIS EXTENDING W TO 27N66W. STRONG SUBSIDENCE AND DRY 
STABLE AIR ALOFT DOMINATE THE ATLC WATERS GIVING THE AREA FAIR 
WEATHER TONIGHT. THE FRONT IS EXPECTED TO EXTEND FROM JUST E OF 
BERMUDA TO E CUBA BY TONIGHT BEFORE STALLING THEN DISSIPATING BY 
MON. 

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

$$
PAW