000 AXNT20 KNHC 191813 CCA TWDAT TROPICAL WEATHER DISCUSSION...CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE APR 19 2016 CORRECTED DISCUSSION HEADER 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...ITCZ/MONSOON TROUGH... A WEAK N ILL-DEFINED TROUGH IS ANALYZED ACROSS WESTERN AFRICA TO THE COAST OF THE BORDER BETWEEN SIERRA LEONE AND LIBERIA WHERE IT TRANSITIONS TO THE ITCZ OVER THE TROPICAL EASTERN ATLC SW TO 03N18W TO 03N25W TO 02N31W TO 02N44W TO S OF THE EQUATOR NEAR 50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG AND S OF THE ITCZ BETWEEN 41W-50W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF ITCZ BETWEEN 45W-49W...AND ALSO WITHIN 60 NM N OF ITCZ BETWEEN 25W-28W. ...DISCUSSION... GULF OF MEXICO... AN UPPER SHORTWAVE TROUGH IS MOVING E OVER EASTERN TEXAS. IT SUPPORTS A SURFACE TROUGH ALONG IMMEDIATE TEXAS COAST FROM GALVESTON TO JUST NE OF BROWNSVILLE THE EARLIER WEAK 1017 MB LOW NEAR 27N93W HAS WEAKENED TO A TROUGH FROM 29N92W TO 27N94W. SATELLITE IMAGERY SHOWS SCATTERED SHOWERS AND WEAKENING ISOLATED TSTMS FROM 23N-28N BETWEEN 91W-96W. A SECOND SHORTWAVE UPPER TROUGH IS JUST INLAND NE MEXICO. THE DIFFLUENT FLOW PATTERN ALOFT TO ITS E IS PRODUCING LARGE CLUSTERS OF SCATTERED TSTMS WITH FREQUENT LIGHTNING AND POSSIBLE GUSTY WINDS CONFINED TO THE SW GULF S OF 23N BETWEEN 91W-93W. THE DIURNAL SURFACE TROUGH HAS MOVED W DURING THE MORNING...AND EXTENDS FROM NEAR 24N96W TO 19N95W. THIS FEATURE IS ALSO AIDING IN THE AFOREMENTIONED SCATTERED TSTM ACTIVITY. A SURFACE RIDGE REMAINS OVER THE EASTERN GULF AND WESTERN ATLC ANCHORED BY A 1024 MB HIGH OVER SOUTHERN GEORGIA. THE HIGH IN COMBINATION WITH DRY SINKING AIR ALOFT TO THE E OF THE WESTERN GULF CONVECTIVE ACTIVITY IS MAINTAINING GENERALLY CLEAR SKIES OVER THE EASTERN GULF. THE SURFACE RIDGE WILL PERSIST THROUGH THU...THEN SLIDE EASTWARD FRI AS A WEAK COLD FRONT ENTERS THE NW GULF. CARIBBEAN SEA... NEAR ZONAL WESTERLY FLOW ALOFT DOMINATES THE CARIBBEAN THIS MORNING. AN UPPER TROUGH OVER THE WESTERN ATLC COMBINED WITH AN UPPER RIDGE OVER S AMERICA/W TROPICAL ATLC IS GENERATING A JET STREAK OVER THE NE CARIBBEAN INTO THE CENTRAL ATLC. A COLD FRONT OVER THE CENTRAL ATLC EXTENDS A DISSIPATING STATIONARY FRONT SW TO THE LEEWARD/VIRGIN ISLANDS AREA. THE COMBINATION OF SURFACE TO LOW-LEVEL CONVERGENCE ALONG THE FRONT WITH JET DYNAMICS OVER THE NE CARIBBEAN IS SETTING OFF SCATTERED TO NUMEROUS SHOWERS AND ISOLATED TSTMS OVER MUCH OF THE NE CARIBBEAN INCLUDING THE LEEWARD ISLANDS...AND IMMEDIATE SURROUNDING WATERS. SCATTERED SHOWERS AND TSTMS HAVE DEVELOPED OVER PUERTO RICO AS DAYTIME HEATING HAS PLAYED A ROLE IN THE DEVELOPMENT OF THIS ACTIVITY. MAINLY MID TO HIGH CLOUDS ARE OVER THE SE CARIBBEAN WITH ONLY ISOLATED SHOWERS AND WEAK ISOLATED TSTMS NOTED THERE. SCATTERED SHOWERS AND ISOLATED TSTMS ARE SEEN TO THE SSW OF PUERTO RICO WITHIN 60 NM OF A LINE FROM 16N65W TO 16N71W. THE SURFACE RIDGE OVER THE EASTERN GULF OF MEXICO AND THE WESTERN ATLC EXETNDS TO THE FAR NW CARIBBEAN. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN WITH GENERALLY FAIR WEATHER CONDITIONS THIS AFTERNOON. MODERATE TO FRESH TRADE WINDS WILL PERSIST ACROSS THE BASIN THROUGH THU NIGHT. NE WINDS ARE EXPECTED TO PULSE FRESH TO STRONG EACH NIGHT S OF HISPANIOLA AND ON THE APPROACH TO THE WINDWARD PASSAGE THROUGH THU NIGHT. HISPANIOLA... THE SOUTHERN PORTION OF THE CENTRAL ATLC COLD FRONT EXTENDS SW AS A DISSIPATING STATIONARY FRONT TO THE VIRGIN/LEEWARD ISLANDS AREA. LOW-LEVEL MOISTURE SPINNING OFF THE FRONTAL BOUNDARY IS BEING ADVECTING WESTWARD IN THE TRADE WIND FLOW TO THE S OF HISPANIOLA. ISOLATED SHOWERS ARE POSSIBE NEAR THE SOUTHERN COAST OF HISPANIOLA THROUGH THU. SATELLITE IMAGERY IS SHOWING SCATTERED TO BROKEN LOW CLOUDS DEVELOPING INTO HIGH TOP CLOUDS. WITH DAYTIME HEATING UNDERWAY...SOME OF THESE CLOUDS ARE LIKELY TO LEAD TO SHOWERS AND TSTMS DURING THE REST OF THE AFTERNOON. ATLANTIC OCEAN... A SURFACE RIDGE COVERS THE W ATLC W OF ABOUT 68W TO THE NW CARIBBEAN...AND TO OVER THE E GULF OF MEXICO ANCHORED BY A 1024 MB HIGH OVER S GEORGIA. A BROAD UPPER TROUGH COVERS THE WESTERN AND CENTRAL ATLC WITH A MEAN TROUGH AXIS EXTENDING ROUGHLY FROM 32N54W SW TO 23N66W TO NEAR 23N77W. IT IS SUPPORTING A COLD FRONT THAT EXTENDS FROM A TRIPLE POINT N OF THE AREA THROUGH 32N44W... AND SW TO 25N50W TO 21N58W WHERE IT BECOMES A DISSIPATING STATIOANRY FRONT TO THE LEEWARD ISLANDS. A RE- ENFORCING SURGE IN THE FORM OF A SURFACE TROUGH TRAILS THE FRONT EXTENDING FROM A 1003 MB LOW NEAR 33N57W SW TO 28N60W TO 25N64W. UPPER DIFFLUENT ALOFT E OF THE UPPER TROUGH CONTINUES TO GENERATE SCATTERED TO NUMEROUS SHOWERS/ISOLATED TSTMS WITHIN 150-180 NM OF A LINE FROM THE LEEWARD/VIRGIN ISLANDS NEAR 18N62W ALONG 23N52W TO 32N41W. A WEAK SURFACE RIDGE COVERS THE REMAINDER OF THE ATLC ANCHORED BY A 1021 MB HIGH NW OF THE AZORES AND ANOTHER 1021 MB HIGH NEAR 29N30W. THE CENTRAL ATLC COLD FRONT WILL MOVE SLOWLY EASTWARD THROUGH WED WHILE TRANSITIONING INTO A SURFACE TROUGH. ANOTHER COLD FRONT WILL QUICKLY SWEEP ACROSS THE NE WATERS ON WED. SURFACE RIDGING IS FORECAST TO BUILD SEWD ACROSS THE W ATLC IN THE WAKE OF THE FRONTS AND WEAKEN THU NIGHT THROUGH FRI NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE