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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 051153
TWDAT 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
705 AM EST THU MAR 05 2015

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
1130 UTC.

...SPECIAL FEATURES...

...GALE WARNING FOR THE SW CARIBBEAN... 

A GALE WARNING IS IN EFFECT FOR COASTAL WATERS OF COLOMBIA FROM 
10.5N TO 13.5N BETWEEN 74W AND 77W WITH SEAS RANGING BETWEEN 10 
AND 15 FT. THESE CONDITIONS ARE FORECAST THROUGH THURSDAY 
AFTERNOON...RESUMING AGAIN DURING THE NIGHT HOURS. PLEASE SEE 
THE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ 
FZNT02 KNHC FOR MORE DETAILS.

...GALE WARNING FOR THE GULF OF MEXICO... 

A GALE WARNING IS IN EFFECT FOR THE NW GULF ASSOCIATED WITH A 
COLD FRONT THAT MOVED OFF THE LOUISIANA AND TEXAS COAST THIS 
MORNING. GALE CONDITIONS ARE FORECAST TO CONTINUE W OF THE FRONT 
UNTIL FRIDAY NIGHT...AS THE FRONT MOVES E-SE. PLEASE SEE THE 
LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ 
FZNT02 KNHC FOR MORE DETAILS.  

...ITCZ/MONSOON TROUGH...                                      

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL 
ATLANTIC NEAR 05N09W TO 04N13W WHERE THE ITCZ BEGINS AND 
CONTINUES ALONG THE EQUATOR TO 30W THEN TO THE COAST OF NORTHERN 
BRAZIL NEAR 01S50W. SCATTERED MODERATE CONVECTION AND ISOLATED 
TSTMS ARE FROM THE EQUATOR TO 06S BETWEEN 12W AND 34W...AND FROM 
THE EQUATOR TO 06N W OF 42W.

...DISCUSSION...

GULF OF MEXICO...      

A BROAD RIDGE ANCHORED OVER THE CENTRAL ATLC N OF 30N CONTINUES 
TO EXTEND AN AXIS SW ACROSS THE FLORIDA PENINSULA AND THE 
EASTERN GULF. SURFACE LOW PRESSURE IS BUILDING OVER THE WESTERN 
BASIN ASSOCIATED WITH A COLD FRONT THAT CAME OFF THE LOUISIANA 
AND TEXAS COASTS THIS MORNING. THE COLD FRONT EXTENDS FROM 
29N92W SW TO NE MEXICO NEAR 25N97W WITH GALE FORCE WINDS W OF 
THE BOUNDARY. SE TO S WIND FLOW OF 10 TO 15 KT IS ELSEWHERE E OF 
THE COLD FRONT. ALOFT...SOUTHWESTERLY FLOW COVERS THE BASIN WITH 
WATER VAPOR IMAGERY INDICATING RELATIVELY STRONG 
SUBSIDENCE...EXCEPT FOR THE NW GULF WHERE MOISTURE IS BEING 
ADVECTED FROM THE EPAC WATERS. OVERALL STABLE CONDITIONS ALOFT 
AND AT THE SURFACE E OF THE FRONT FAVOR FAIR WEATHER AND CLEAR 
SKIES DOMINATE. OVER THE NW GULF...LOW-LEVEL MOISTURE 
CONVERGENCE AND A DIFFLUENT ENVIRONMENT ALOFT ASSOCIATED WITH 
THE COLD FRONT SUPPORT BROKEN TO OVERCAST SKIES WITH POSSIBLE 
ISOLATED SHOWERS. IN ADDITION...FOG AND HAZE IS BEING REPORTED N 
OF 25N W OF 90W AND OVER THE FLORIDA PANHANDLE...COINCIDING WITH 
MEDIUM TO HIGH GOES-13 IFR PROBABILITIES OF FOG. THE COLD FRONT 
WILL EXTEND FROM THE FLORIDA PANHANDLE SW TO THE BAY OF CAMPECHE 
TONIGHT AND WILL START DISSIPATING OVER CENTRAL FLORIDA FRIDAY 
NIGHT. GALE FORCE WINDS ARE FORECAST TO CONTINUE W OF THE FRONT 
THROUGH FRIDAY NIGHT. SEE SPECIAL FEATURES ABOVE.

CARIBBEAN SEA...    

BROAD UPPER LEVEL TROUGHING IS OBSERVED ON WATER VAPOR IMAGERY 
COVERING THE CENTRAL AND EASTERN CARIBBEAN WHILE A RIDGE COVERS 
THE REMAINDER BASIN. RELATIVELY DRY AND STABLE AIR IS ASSOCIATED 
WITH THIS UPPER WIND PATTERN WHICH CONTINUE TO PROVIDE OVERALL 
FAIR CONDITIONS ACROSS THE BASIN. AT THE LOWER LEVELS...MOISTURE 
PATCHES ARE OBSERVED MAINLY S OF 15N AND OVER THE NW 
CARIBBEAN...POSSIBLY ENHANCING ISOLATED SHOWERS. A SHALLOW 
AIRMASS IS ALSO OBSERVED MOVING ACROSS PUERTO RICO AND ADJACENT 
WATERS INCREASING THE CHANCE OF ISOLATED SHOWERS DURING THE 
MORNING AND AFTERNOON HOURS. TRADE WINDS OF 20 TO 25 KT ARE OVER 
THE EASTERN AND CENTRAL BASIN...INCREASING TO GALE FORCE WINDS 
ALONG THE COAST OF COLOMBIA. PLEASE SEE THE SPECIAL FEATURES 
SECTION ABOVE FOR MORE DETAILS. TRADES OF 15 KT ARE ELSEWHERE. 

...HISPANIOLA...                                                 

DEEP LAYER DRY AIR IS OVER HISPANIOLA AND IS EXPECTED TO PREVAIL 
THROUGHOUT SUNDAY MORNING THUS FAVORING FAIR WEATHER CONDITIONS.

ATLANTIC OCEAN...

A NARROW UPPER LEVEL TROUGH OVER THE CENTRAL ATLC EXTENDING SW 
TO A BASE OVER THE SW CARIBBEAN CONTINUE TO SUPPORT A FRONT 
ANALYZED AS A DISSIPATING COLD FRONT FROM 30N41W SW TO 26N49W. 
NO CONVECTION IS ASSOCIATED WITH IT. OTHERWISE...THE REMAINDER 
ATLC W AND E OF THE FRONTAL BOUNDARY IS UNDER THE INFLUENCE OF A 
BROAD SURFACE RIDGE ANCHORED BY A PAIR OF HIGH PRESSURE CENTERS 
N OF THE AREA OF DISCUSSION. THE NEXT COLD FRONT ENTERS THE SW N 
ATLC WATERS FRIDAY MORNING.

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

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NR