000 AXNT20 KNHC 270544 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON MAY 27 2013 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 10N14W TO 05N25W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N25W TO 05N38W TO 02N50W. ISOLATED MODERATE TO STRONG CONVECTION IS FROM 05N-10N BETWEEN 10W-21W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER SE TEXAS WITH AXIS EXTENDING SOUTHWARD ALONG 100W TO A BASE OVER SOUTHERN MEXICO. MIDDLE TO UPPER LEVEL DIFFLUENCE IS MAXIMIZED EAST OF THE TROUGHING GENERATING INCREASED CLOUDINESS AND POSSIBLE ISOLATED SHOWERS AND TSTMS S OF 25N W OF 90W. OTHERWISE...WEST-NORTHWESTERLY FLOW REMAINS THE PRIMARY INFLUENCE ACROSS THE EASTERN GULF WITH ONLY A FEW EASTWARD MOVING ISOLATED SHOWERS OCCURRING NW OF KEY WEST FLORIDA...AND ACROSS AN AREA N OF 27N BETWEEN 85W-90W. THESE AREAS OF PRECIPITATION ARE FOUND WITHIN E-SE SURFACE WINDS AROUND THE WESTERN PERIPHERY OF A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED IN THE SW NORTH ATLC NEAR 33N68W. THE SURFACE RIDGE IS EXPECTED TO REMAIN IN PLACE ACROSS THE GULF THROUGH WEDNESDAY WITH E-SE WINDS OCCURRING IN THE RANGE OF 10 TO 20 KT. CARIBBEAN SEA... UPPER LEVEL TROUGHING IS LOCATED BETWEEN TWO ANTICYCLONIC CIRCULATIONS OVER THE CENTRAL CARIBBEAN WITH AXIS ALONG 70W. WEST-NORTHWESTERLY FLOW IS NOTED W OF 70W WITH WATER VAPOR INDICATING AN OVERALL DRY AND STABLE ENVIRONMENT. ONLY A FEW ISOLATED SHOWERS AND TSTMS ARE OCCURRING OVER THE GULF OF HONDURAS AND OFFSHORE OF CENTRAL AMERICA SW OF A LINE FROM 20N87W TO 15N80W. THIS CONVECTION CONTINUES TO BE ENHANCED BY UPPER LEVEL DIFFLUENCE IN ASSOCIATION WITH THE UPPER LEVEL ANTICYCLONE. EAST OF 70W...MOIST SOUTHWESTERLY FLOW CONTINUES TO AID IN GENERATING SCATTERED SHOWERS AND TSTMS EAST OF A LINE FROM 20N60W TO THE CENTRALLY LOCATED ABC ISLAND OF CURACAO NEAR 12N69W. OTHERWISE...THE UPPER LEVEL TROUGHING IS PROVIDING MOISTURE OVER THE GREATER ANTILLES WITH WIDELY SCATTERED SHOWERS CONTINUING TO LESSEN IN COVERAGE DURING THE LAST 6 HOURS AS THE PRIOR EVENING CONVECTION DIMINISHES. E-SE TRADES ARE EXPECTED TO PERSIST THROUGH THURSDAY AS THE OVERALL SYNOPTIC PATTERN CHANGES LITTLE OVER THE NEXT FEW DAYS. HISPANIOLA... CURRENTLY A FEW DIMINISHING SHOWERS ARE NOTED ON SATELLITE IMAGERY ACROSS THE ISLAND AS LATE AFTERNOON AND EVENING CONVECTION COMES TO AN END. AN UPPER LEVEL TROUGH STILL REMAINS OVER HISPANIOLA AND THE SURROUNDING ADJACENT COASTAL WATERS AND THIS AGAIN WILL PROVIDE FOR AN OVERALL UNSTABLE ENVIRONMENT BY MONDAY AFTERNOON INTO THE EVENING HOURS. SCATTERED SHOWERS AND ISOLATED TSTMS ARE EXPECTED TO INITIATE DUE TO PEAK DAYTIME HEATING AND INSTABILITY. ATLANTIC OCEAN... A DEEP LAYERED LOW CENTERED OVER NEW BRUNSWICK CANADA EXTENDS TROUGHING SOUTHWARD OVER MUCH OF THE SW NORTH ATLC TO A BASE OVER THE NORTH-CENTRAL CARIBBEAN SEA. WATER VAPOR IMAGERY INDICATES MOSTLY WEST-NORTHWESTERLY FLOW WEST OF 64W THAT IS PROVIDING AN OVERALL QUIET EVENING FOR THE THE SW NORTH ATLC WATERS. A FEW ISOLATED SHOWERS ARE HOWEVER MOVING ON EASTERLY WINDS ON THE SOUTHWESTERN PERIPHERY OF A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED NEAR 33N68W. FARTHER EAST...THE UPPER LEVEL TROUGHING SUPPORTS A STATIONARY FRONT ANALYZED INTO THE DISCUSSION AREA NEAR 32N62W THAT EXTENDS SW TO 28N67W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC ARE UNDER THE INFLUENCE OF A BROAD AND EXPANSIVE SURFACE RIDGE ANCHORED BY A 1037 MB HIGH CENTERED W-NW OF THE AZORES NEAR 42N38W. THE ONLY CONCENTRATED AREA OF PRECIPITATION SURROUNDING THIS RIDGE IS LOCATED ON THE SOUTHWESTERLY PERIPHERY WITH ISOLATED SHOWERS AND TSTMS OCCURRING S OF 25N BETWEEN 50W- 65W...DUE TO MAXIMIZED MIDDLE TO UPPER LEVEL DIFFLUENCE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN