000 AXNT20 KNHC 230005 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EST TUE APR 22 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...THE ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL BORDER SECTIONS OF GUINEA-BISSAU AND SENEGAL FROM 12N16W TO 4N24W. THE ITCZ EXTENDS FROM 2N27W AND CROSSES THE EQUATOR NEAR 39W TO THE COAST OF SOUTH AMERICA NEAR 2S44W. SCATTERED STRONG CONVECTION WAS NOTED WITHIN 120 NM OF 5N15W. A SURFACE TROUGH IS ALONG 3N7W TO THE EQUATOR AT 17W. ...DISCUSSION... ...THE GULF OF MEXICO... A MID TO UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION OVER SE ALABAMA THROUGH 29N90W TO A BASE NEAR 22N97W. THERE WERE SEVERAL WEAK CYCLONIC CIRCULATIONS WITHIN THE TROUGH OVER THE WEST-CENTRAL GULF. STRONG SUBSIDENCE WAS SWEEPING ALONG THE BACKSIDE OF THE TROUGH OVER THE NW GULF OF MEXICO. MID TO UPPER LEVEL MOISTURE WAS SWEEPING OVER THE GULF E OF THE TROUGH IN FAIRLY STRONG WSW FLOW ALOFT. AT THE SURFACE...A PAIR OF WEAK 1017 MB HIGH PRESSURE AREAS WERE NOTED NEAR 28N92W AND IN THE VICINITY OF TAMPICO MEXICO. A COLD FRONT WAS JUST INLAND ALONG THE UPPER TEXAS AND LOUISIANA COAST WITH A PRE-FRONTAL TROUGH ALONG THE IMMEDIATE COAST OF LOUISIANA. SKIES WERE GENERALLY FAIR OVER THE GULF WITH PATCHES OF LOW AND MID CLOUDS. THE WEAK PRESSURE PATTERN MANIFESTED IN LIGHT WINDS OVER THE ENTIRE GULF WITH BUOYS REPORTING SEAS OF 1 TO 2 FEET THROUGHOUT. ...THE CARIBBEAN SEA... AN UPPER LEVEL RIDGE EXTENDS FROM NORTHWESTERN VENEZUELA... ACROSS NORTHERN COLOMBIA...THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO THE COAST OF NICARAGUA NEAR 13N84W. S TO SW FLOW ALOFT WAS NOTED S OF THE RIDGE AXIS WITH STRONG WNW FLOW NOTED N OF THE AXIS ACROSS CUBA...HISPANIOLA AND PUERTO RICO. UPPER LEVEL MOISTURE WAS CURVING TO THE NORTH AND EAST ACROSS THE BASIN S OF 15N. THE BROKEN TO OVERCAST HIGH CLOUDS NOTED ABOVE MASKED PATCHES OF BROKEN LOW AND MIDDLE LEVEL CLOUDS AND POSSIBLE LOW TOPPED SHOWERS MOVING WESTWARD IN TRADE WIND FLOW ACROSS THE BASIN. ISOLATED THUNDERSTORMS WERE ERUPTING OVER JAMAICA....EXTREME SE CUBA AND NORTH-CENTRAL PORTIONS OF THE DOMINICAN REPUBLIC WHERE OROGRAPHIC LIFT CONTRIBUTED TO THE ACTIVITY. SCATTEROMETER DATA INDICATED SUB-NORMAL TRADE WINDS ACROSS THE BASIN WITH A LARGE AREA OF 5 TO 10 KT WINDS NOTED OVER THE BASIN WEST OF 75W. THE LIGHT WINDS SHIFTED FROM THE EAST TO LIGHT NORTHWESTERLY IN THE VICINITY OF A SURFACE TROUGH WHICH EXTENDED FROM THE EXTREME SE COAST OF CUBA THROUGH 18N84W TO THE GULF OF HONDURAS. R TO SE WINDS OF 10-15 KT PREVAILED OVER THE CARIBBEAN E OF 75W. ...HISPANIOLA... STRONG WEST-NORTHWEST FLOW ALOFT SWEPT ACROSS CUBA AND HISPANIOLA TO PUERTO RICO AMIDST STRONG DEEP LAYERED SUBSIDENCE IN THE AREA. THE PROXIMITY OF A WEAK COLD FRONT AND SURFACE TROUGH ACROSS EXTREME NORTHERN PORTIONS OF THE ISLAND TRIGGERED ANOTHER ROUND OF AFTERNOON THUNDERSTORMS NEAR PUERTO PLATA AND LORNA DE CABRERA. BROKEN TO OVERCAST LOW AND MID CLOUDS COVERED THE REMAINDER OF HAITI AND THE DOMINICAN REPUBLIC EXTENDING OVER THE SOUTHEAST BAHAMAS. THE PRESENCE OF THE TROUGH/FRONTAL REMNANT IN THE AREA OVER THE NEXT DAY OR SO WILL CONTINUE TO ALLOW FOR ENHANCED THUNDERSTORM ACTIVITY ACROSS THE ISLAND. ...THE ATLANTIC OCEAN... A MID TO UPPER LEVEL CYCLONIC CIRCULATION NEAR 37N60W WAS ACCELERATING OUT TO THE NE WITH AN ATTENDANT TROUGH EXTENDING SOUTHWARD THROUGH 31N60W TO A BASE NEAR 23N67W. STRONG SUBSIDENCE WAS NOTED WITHIN 11120-180 NM EITHER SIDE OF THE TROUGH. THE TROUGH WAS PROVIDING WANING SUPPORT FOR A COLD FRONT THAT PASSED THROUGH 32N61W TO 25N65W TO THE EXTREME NORTH COAST OF THE DOMINICAN REPUBLIC. A SURFACE TROUGH CONTINUES FROM THE FRONT...ACROSS NORTHERN HAITI...THROUGH THE WATERS THAT ARE BETWEEN HAITI...CUBA...AND JAMAICA TO THE NW CARIBBEAN SEA. A POST-FRONTAL TROUGH IS ALONG 31N65W 24N70W TO 23N72W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WAS NOTED WITHIN 90-120 NM E OF THE COLD FRONT N OF 26N. MID TO UPPER LEVEL MOISTURE WAS STREAMING TO THE EAST OF THE TROUGH AND FRONT COVERED THE ATLANTIC N OF 22N BETWEEN 35W AND 62W. A MIDDLE LEVEL TO UPPER LEVEL SHEARED TROUGH IS ALONG 27N18W THROUGH 22N30W TO A BASE NEAR 13N47W. COMPARATIVELY DRIER AIR IN SUBSIDENCE...APPARENT IN WATER VAPOR IMAGERY...IS WITHIN 300 NM TO 600 NM TO THE NORTHWEST OF THE LINE FROM 24N20W TO 10N45W. A 1024 MB HIGH PRESSURE CENTER IS NEAR 34N31W. A COLD FRONT ENTERED THE AREA NEAR 32N22W...BECAME STATIONARY NEAR 29N35W AND EXITED THE AREA NEAR 32N43W. SURFACE ANTICYCLONIC WINDS COVERED THE REMAINDER OF THE ATLANTIC OCEAN AND THE CARIBBEAN SEA TO THE NORTH OF 10N BETWEEN AFRICA AND 60W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB