000
AXNT20 KNHC 120559
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
105 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...ITCZ...

THE ITCZ IS ANALYZED FROM LIBERIA NEAR 7N11W 4N14W 2N22W THEN 
ALONG THE EQUATOR BETWEEN 28W-41W THEN S OF THE EQUATOR INTO 
BRAZIL. SCATTERED/NUMEROUS STRONG CONVECTION WITHIN 75 NM OF THE 
ITCZ BETWEEN 37W-44W. CLUSTERS OF SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION ARE WITHIN 120 NM S OF THE ITCZ BETWEEN 
20W-26W AND FROM 5N TO THE EQUATOR BETWEEN 32W-48W. 

...DISCUSSION...

GULF OF MEXICO...
A BROAD FLAT UPPER TROUGH COVERS THE E CONUS AND GULF OF MEXICO 
GIVING THE GULF SW FLOW ALOFT SUPPORTING A COLD FRONT IN THE W 
ATLC TO OVER W CUBA BECOMING A STATIONARY FRONT THAT AT 12/0300 
UTC EXTENDS ACROSS THE YUCATAN CHANNEL FROM 22N84W TO 21N88W AND 
OVER THE YUCATAN PENINSULA. DENSE LOW LEVEL CLOUDS WITH 
SCATTERED SHOWERS COVER THE GULF S OF 27N BANKING ALONG THE THE 
SIERRA MADRE MOUNTAINS IN MEXICO AND OVER PORTIONS OF CENTRAL 
AMERICA. A SURFACE RIDGE DOMINATES THE REMAINDER OF THE GULF 
ANCHORED AT 12/0300 UTC BY A 1031 MB HIGH OVER E TEXAS. HIGH 
PRESSURE WILL REMAIN IN CONTROL OF THE GULF THROUGH THE WEEKEND 
INTO THE FIRST OF NEXT WEEK.

CARIBBEAN SEA...
AS OF 12/0300 UTC...A STATIONARY FRONT EXTENDS THROUGH THE 
YUCATAN CHANNEL FROM 22N84W TO 21N88W OVER THE YUCATAN PENINSULA 
TO BELIZE. DENSE LOW LEVEL CLOUDS WITH SCATTERED SHOWERS ARE W 
OF THE FRONT INTO THE GULF OF MEXICO AND WITHIN 60 NM S AND E OF 
THE FRONT INTO THE CARIBBEAN. 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 13N-20N BETWEEN 65W-72W. TRADE WINDS ARE 
EXPECTED TO DIMINISH SLIGHTLY SAT AS THE FRONT ACROSS THE 
YUCATAN CHANNEL WILL EXTEND FROM CENTRAL CUBA TO THE GULF OF 
HONDURAS BY SAT AFTERNOON THEN STALL AND DISSIPATE FROM THE 
WINDWARD PASSAGE TO N COAST OF HONDURAS 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 
12/0300 UTC EXTENDS INTO THE W ATLC THROUGH 32N73W ACROSS THE 
BAHAMAS NEAR 25N77W TO OVER W CUBA NEAR 23N81W INTO THE GULF OF 
MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 
75/90 NM E OF THE FRONT N OF 27N WITH DENSE LOW LEVEL CLOUDS AND 
SCATTERED SHOWERS S OF 27N 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 26N48W. A SURFACE RIDGE COVERS THE E 
AND CENTRAL ATLC ANCHORED BY A 1031 MB HIGH S OF THE AZORES NEAR 
33N25W WITH THE RIDGE AXIS EXTENDING SW ALONG 28N41W THEN W TO 
27N70W. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT DOMINATE THE 
ATLC WATERS GIVING THE AREA FAIR WEATHER TONIGHT. THE FRONT IS 
EXPECTED TO EXTEND FROM NEAR BERMUDA TO E CUBA BY SAT AFTERNOON 
BEFORE STALLING THEN DISSIPATING BY MON. 

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

$$
PAW