000 AXNT20 KNHC 150550 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN APR 15 2012 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. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 06N10W TO 03N14W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 03N14W TO THE EQUATOR NEAR 33W THEN TO 02S45W. SCATTERED MODERATE CONVECTION IS FROM 03N-07N BETWEEN 09W-13W...AND FROM THE EQUATOR TO 03N BETWEEN 30W-41W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES MOSTLY DRY AIR AND SUBSIDENCE IS OVER THE GULF THIS EVENING AS AN UPPER LEVEL RIDGE WITH AXIS ALONG 91W CONTINUES TO AMPLIFY NORTHWARD OVER THE SE CONUS. THE OVERALL SUBSIDENT CONDITIONS FILTER DOWN TO THE LOWER LEVELS OF THE ATMOSPHERE AS A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH REMAINS CENTERED OVER THE SW NORTH ATLC AND EXTENDS INFLUENCE WESTWARD OVER THE BASIN. STRONG EAST-SOUTHEASTERLY WINDS ARE NOTED ACROSS THE BASIN AS MOIST LOW-LEVEL RETURN FLOW CONTINUES TO FUEL A DEEP SURFACE LOW PRESSURE OVER THE CENTRAL PLAINS AND THE ASSOCIATED ONGOING CONVECTION THIS EVENING OVER KANSAS... NEBRASKA...AND IOWA. OVER THE NEXT 36 TO 48 HOURS...THE PRESSURE GRADIENT BETWEEN THE STRONG SURFACE LOW AND RIDGE ACROSS THE GULF WILL PERSIST UNTIL MONDAY WHEN THE GRADIENT WILL BEGIN TO RELAX GRADUALLY DUE TO A WEAK FRONTAL BOUNDARY EMERGING OFF THE TEXAS AND LOUISIANA COASTS. THE FRONTAL TROUGHING WILL REMAIN WEAK ACROSS THE NORTHERN GULF THROUGH TUESDAY INTO WEDNESDAY WITH WINDS GENERALLY IN THE RANGE OF 10 TO 15 KT. CARIBBEAN SEA... WEST-SOUTHWESTERLY UPPER LEVEL FLOW IS OVER THE CARIBBEAN THIS EVENING WITH UPPER LEVEL MOISTURE STREAMING NORTHEASTWARD OFF THE SOUTH AMERICAN CONTINENT DUE TO EARLIER EVENING CONVECTION ACROSS PORTIONS OF NORTHERN COLOMBIA AND VENEZUELA. WATER VAPOR IMAGERY INDICATES FAIRLY DRY AIR OVER THE CARIBBEAN AND THIS IS RESULTING IN A LACK OF ANY SIGNIFICANT DEEP CONVECTION. OVER THE NE CARIBBEAN...A COLD FRONT EXTENDS FROM THE CENTRAL ATLC NEAR 20N60W TO 17N68W. LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE FRONT IS GENERATING ISOLATED SHOWERS N OF 15N E OF 70W. MOISTURE LINGERS TO THE WEST FROM 15N-20N BETWEEN 72W-83W WITH ISOLATED SHOWERS POSSIBLE THROUGH THE OVERNIGHT HOURS. OTHERWISE...EAST-NORTHEAST TRADES ARE FORECAST TO PERSIST THROUGH SUNDAY...WITH STRONGER NE FLOW BLEEDING THROUGH THE WINDWARD AND MONA PASSAGES AS THE PRESSURE GRADIENT STRENGTHENS BETWEEN 60W-80W. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS OVER THE CENTRAL ATLC WITH AXIS EXTENDING FROM 35N57W TO 30N60W STRETCHING SW TO 25N75W. THIS TROUGH SUPPORTS A COLD FRONT ANALYZED INTO THE DISCUSSION AREA NEAR 32N50W TO 20N60W AND INTO THE NE CARIBBEAN SEA. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 180 NM EITHER SIDE OF THE FRONT N OF 24N...AND ISOLATED SHOWERS WITHIN 120 NM EITHER SIDE OF THE FRONT S OF 24N. ELSEWHERE OVER THE REMAINDER OF THE SW NORTH ATLC...HIGH PRESSURE CONTINUES TO BUILD E-SE AS A 1028 MB HIGH CENTERED NEAR 32N73W IS FORECAST TO REMAIN IN CONTROL THROUGH WEDNESDAY. LOW-LEVEL MOISTURE IS EXPECTED TO ADVECT AROUND THE SOUTHERN PERIPHERY OF THE RIDGE WITH POSSIBLE ISOLATED SHOWERS MOVING QUICKLY ACROSS THE BAHAMAS AND INLAND OVER THE EASTERN FLORIDA PENINSULA COAST. FARTHER EAST ACROSS THE EASTERN ATLC...A RIDGE REMAINS THE DOMINATE INFLUENCE ANCHORED BY A 1032 MB HIGH CENTERED OVER THE AZORES NEAR 38N29W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN