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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 041139
TWDAT 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
705 AM EST WED MAR 04 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 COLOMBIA COASTAL WATERS FROM 
FROM 11N TO 13N BETWEEN 74W AND 76W WITH ASSOCIATED SEAS RANGING 
BETWEEN 9 TO 12 FT. THESE CONDITIONS ARE FORECAST THROUGH 
WEDNESDAY AFTERNOON...RESUMING AGAIN DURING THE NIGHT HOURS. 
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 07N12W SW TO 04N18W WHERE THE ITCZ BEGINS AND 
CONTINUES ALONG 01S32W TO THE COAST OF NORTHERN BRAZIL NEAR 
02S44W. ISOLATED SHOWERS ARE WITHIN 100 NM EITHER SIDE OF THE 
ITCZ W OF 24W. 

...DISCUSSION...

GULF OF MEXICO...      

WATER VAPOR IMAGERY INDICATES RELATIVELY STRONG SUBSIDENCE IN 
ASSOCIATION WITH A BROAD MIDDLE TO UPPER LEVEL RIDGE. AT THE 
SURFACE...A 1028 MB HIGH PRESSURE CENTER OVER THE W ATLC NEAR 
35N59W EXTENDS A RIDGE AXIS SW ACROSS THE FLORIDA PENINSULA AND 
THE GULF...THUS PROVIDING WITH SE WIND FLOW OF 10 TO 15 KT. WITH 
OVERALL STABLE CONDITIONS ALOFT AND AT THE SURFACE...FAIR 
WEATHER AND CLEAR SKIES DOMINATE S OF 26N. HOWEVER...LINGERING 
SHALLOW MOISTURE ADVECTED FROM THE CARIBBEAN SUPPORTS FOG OVER 
THE NW GULF N OF 26N W OF 90W AND OVER THE NE GULF N OF 29N E OF 
88W...THIS COINCIDING WITH MEDIUM TO HIGH GOES-13 IFR 
PROBABILITIES OF FOG. BY EARLY THURSDAY MORNING...THE NEXT COLD 
FRONT IS EXPECTED TO EMERGE OFF THE TEXAS AND LOUISIANA COASTS 
INTRODUCING STRONG TO NEAR GALE FORCE NORTHERLIES...WITH GALE 
FORCE CONDITIONS POSSIBLE...ACROSS THE WESTERN AND NORTH-CENTRAL 
GULF WATERS THROUGH FRIDAY MORNING.

CARIBBEAN SEA...    

BROAD UPPER LEVEL TROUGHING IS OBSERVED ON WATER VAPOR IMAGERY 
WITH AXIS EXTENDING FROM THE CENTRAL ATLC SW THROUGH THE 
NORTHERN LEEWARD ISLANDS TO A BROAD BASE OVER PANAMA. RELATIVELY 
DRY AND STABLE AIR IS EMBEDDED WITHIN THIS TROUGHING ALOFT WHICH 
CONTINUE TO PROVIDE OVERALL FAIR CONDITIONS ACROSS THE BASIN. AT 
THE LOWER LEVELS...MOISTURE PATCHES CONTINUE TO MOVE ACROSS THE 
BASIN THUS ENHANCING SCATTERED SHOWERS OVER THE SE 
CARIBBEAN...PUERTO RICO...HAITI AND CENTRAL AMERICA COASTAL 
WATERS. TRADES OF 15 TO 20 KT DOMINATE OVER THE BASIN...EXCEPT 
FOR THE SW CARIBBEAN WHERE WINDS RANGE FROM 25 TO 30 
KT...INCREASING TO GALE FORCE WINDS ALONG THE COAST OF COLOMBIA. 
PLEASE SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE DETAILS. 
WINDS TO GALE FORCE IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA 
ARE EXPECTED TO PULSE DURING THE LATE NIGHT AND EARLY MORNING 
HOURS DURING THE NEXT THREE DAYS.

...HISPANIOLA...                                                 

SHALLOW MOISTURE IN THE TRADEWIND FLOW SUPPORTS SCATTERED CLOUDS 
ACROSS THE ISLAND...MODEL GUIDANCE INDICATING POSSIBLE SHOWERS 
DURING THIS AFTERNOON. DEEP LAYER DRY AIR IS FORECAST TO MOVE 
OVER HISPANIOLA STARTING THIS EVENING THROUGHOUT SATURDAY 
MORNING THUS FAVORING FAIR WEATHER CONDITIONS.

ATLANTIC OCEAN...    

A MIDDLE TO UPPER LEVEL TROUGH OVER THE CENTRAL ATLC EXTENDING 
SW TO A BASE OVER THE SW CARIBBEAN SUPPORTS A COLD FRONT FROM 
30N49W SW TO 27N67W. SCATTERED SHOWERS ARE OCCURRING AHEAD OF 
THE FRONT N OF 28N W OF 42W. THE FRONT WILL CONTINUE TO 
GRADUALLY WEAKEN THROUGH TONIGHT. OTHERWISE...THE REMAINDER OF 
THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE 
RIDGE ANCHORED BY A 1038 MB HIGH CENTERED NE OF THE AZORES NEAR 
45N13W. 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