000 AXNT20 KNHC 280551 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI MAR 28 2014 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... A STRONG PRESSURE GRADIENT EXISTS ACROSS THE SW CARIBBEAN SEA BETWEEN STRONG HIGH PRESSURE CENTERED ACROSS THE WESTERN NORTH ATLC AND LOWER PRESSURE ACROSS THE NORTHWESTERN SOUTH AMERICAN CONTINENT. WINDS ALONG THE COAST OF COLOMBIA ARE FORECAST TO CONTINUE TO PULSE TO GALE FORCE IN THE EARLY MORNING HOURS WHEN THE PRESSURE GRADIENT IS STRONGEST. GALE FORCE NE TO E WINDS ARE EXPECTED TO OCCUR AGAIN FROM 11N-13N BETWEEN 74W-77W FRIDAY NIGHT INTO EARLY SAT. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 06N11W TO 03N18W TO 01N27W. THE ITCZ BEGINS NEAR 01N27W TO 01S35W TO 04S38W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS FROM 04S-01N BETWEEN 10W-16W AND FROM 01N-06N BETWEEN 12W-25W. ISOLATED MODERATE CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 35W-41W. ...DISCUSSION... GULF OF MEXICO... NEARLY ZONAL WIND FLOW IS NOTED ALOFT OVER THE GULF OF MEXICO. WATER VAPOR IMAGERY INDICATE THE SUBTROPICAL JET STREAM IS ADVECTING MOISTURE AND CLOUDINESS FROM THE EASTERN PACIFIC OVER THE BASIN N OF 24N TO THE FLORIDA PENINSULA. A BROAD RIDGE ANCHORED BY A 1032 MB HIGH OVER THE W ATLC NEAR 34N70W EXTENDS INTO THE GULF AND PROVIDES SOUTHEASTERLY WIND OF 15-20 KT OVER THE WESTERN AND EASTERN BASIN WHILE A TIGHTER PRESSURE GRADIENT OVER THE CENTRAL GULF SUPPORT WINDS UP 30 KT. THESE STRONG WINDS ARE ADVECTING LOW LEVEL MOISTURE ALONG THE NORTH-CENTRAL GULF COAST WHICH ALONG WITH UPPER DIFFLUENCE SUPPORT HEAVY SHOWERS AND TSTMS OVER LOUISIANA...MISSISSIPPI AND PORTIONS OF ALABAMA. SATELLITE IMAGERY SHOW SCATTERED MODERATE CONVECTION N OF 25N WHILE LIGHTING DATA DEPICTS ISOLATED TSTMS FROM 25N-27N BETWEEN 88W-92W. AS THE HIGH PRESSURE CENTER OVER THE W ATLC CONTINUES TO DRIFT NE WINDS OVER THE GULF WILL SHIFT FROM SOUTHEASTERLY TO SOUTHERLY FLOW THUS SUPPORTING A WARM FRONT OVER THE NE GULF FRI NIGHT. BY EARLY SAT MORNING A COLD FRONT IS FORECAST TO MOVE INTO THE NORTHWESTERN GULF WHICH IS EXPECTED TO MOVE ACROSS FLORIDA SAT NIGHT INTO SUN MORNING. CARIBBEAN SEA... NORTHWESTERLY FLOW ALOFT IS OVER THE CARIBBEAN BASIN WITH WATER VAPOR IMAGERY INDICATING RELATIVELY DRY AIR SUBSIDING ACROSS THE REGION. AT THE SURFACE...A SHEAR LINE IS ANALYZED FROM THE NORTHERN DOMINICAN REPUBLIC THROUGH HAITI AND NORTHERN JAMAICA TO 18N80W. SPEED CONVERGENCE OF THE TRADES ALONG THE SHEARLINE IS ENHANCING ISOLATED SHOWERS WITHIN 60 NM S OF IT. A GALE WARNING IS IN EFFECT FOR THE SW CARIBBEAN WATERS OFF THE COAST OF COLOMBIA. THE STRONG PRESSURE GRADIENT CREATED BETWEEN HIGH PRESSURE CENTERED ACROSS THE WESTERN NORTH ATLC AND LOWER PRESSURE ACROSS THE NORTHWESTERN SOUTH AMERICAN CONTINENT IS EXPECTED TO RELAX SOMEWHAT BY SATURDAY AS THE HIGH PRESSURE MOVES NORTHEASTWARD. SEE THE SPECIAL FEATURES SECTION ABOVE FOR DETAILS. EXCEPT FOR THE CENTRAL BASIN WHERE TRADES OF 25 KT DOMINATE...TRADES OF 15-20 KT ARE ELSEWHERE. WINDS OVER THE CENTRAL CARIBBEAN ARE EXPECTED TO SUBSIDE BY SAT MORNING. ...HISPANIOLA... CURRENTLY...A SHEAR LINE IS ANALYZED FROM 19N68W TO THE NORTHERN DOMINICAN REPUBLIC THROUGH HAITI AND JAMAICA TO 18N79W. THIS SHEAR LINE IS ENHANCING ISOLATED SHOWERS ACROSS MUCH OF THE ISLAND...INCLUDING THE SW ADJACENT COASTAL WATERS. THE SHEAR LINE WILL GRADUALLY DISSIPATE OVER THE NEXT 24 HOURS. HOWEVER REMNANT MOISTURE WILL LIKELY ENHANCE SHOWERS OVER HISPANIOLA THROUGH SAT NIGHT. ATLANTIC OCEAN... AN UPPER RIDGE OVER THE N WESTERN ATLC SUPPORTS A BROAD SURFACE RIDGE ANCHORED BY A 1032 MB HIGH OVER THE W ATLC NEAR 34N70W. FARTHER EAST A DEEP LAYER TROUGH SUPPORTS A COLD FRONT OVER THE CENTRAL ATLC EXTENDING INTO THE AREA OF DISCUSSION ALONG 30N49W SW TO 24N58W WHERE IT TRANSITIONS TO A STATIONARY FRONT TO 20N68W AND THEN INTO A SHEARLINE OVER THE NW CARIBBEAN. ISOLATED SHOWERS ARE POSSIBLE WITHIN 100 NM EITHER SIDE OF THE FRONT N OF 24N. OTHERWISE...THE REMAINDER CENTRAL ATLC E OF THE FRONT AND THE EASTERN ATLC N OF 12N IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1032 MB HIGH CENTERED W OF THE AZORES NEAR 38N29W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR