000 AXNT20 KNHC 310544 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI MAY 31 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 14N17W TO 13N19W TO 09N21W TO 06N26W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N26W TO 07N38W TO 05N52W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 03N-09N BETWEEN 11W-20W. ISOLATED MODERATE CONVECTION IS FROM 03N-05N BETWEEN 06W-11W...AND FROM 05N-08N BETWEEN 24W-35W. SCATTERED MODERATE CONVECTION IS FROM 04N-10N BETWEEN 45W-60W. ...DISCUSSION... GULF OF MEXICO... A WEAK UPPER LEVEL TROUGH EXTENDS OVER THE WESTERN GULF WITH AXIS FROM 27N94W TO OVER CENTRAL MEXICO NEAR 20N101W. THIS TROUGHING...WHILE PRODUCING INSIGNIFICANT WEATHER AT THE SURFACE...IS PROVIDING MIDDLE TO UPPER LEVEL STEERING FOR THE REMNANTS OF BARBARA WHICH IS ANALYZED AS A 1006 MB LOW CENTERED IN THE SW GULF NEAR 19N94W. AS THE CIRCULATION CONTINUES TO GRADUALLY DISSIPATE AND BECOME EMBEDDED WITHIN SOUTHEASTERLY FLOW AND RIDGING ACROSS THE NORTHERN AND WESTERN GULF... SCATTERED SHOWERS AND TSTMS ARE OCCURRING TO THE EAST OF THE LOW FOCUSED ALONG A SURFACE TROUGH ANALYZED FROM 18N92W TO 23N90W. THE CONVECTION IS OCCURRING S OF 24N BETWEEN 87W-94W. OTHERWISE...THE REMAINDER OF THE NORTHERN AND EASTERN GULF IS UNDER WESTERLY UPPER LEVEL FLOW AND RELATIVELY QUIETER CONDITIONS THIS EVENING. A WEAK SURFACE TROUGH EMBEDDED WITHIN THE SURFACE RIDGING IS ANALYZED FROM OFF THE WESTERN FLORIDA PENINSULA COAST FROM 25N83W TO 29N94W WITH ISOLATED SHOWERS OCCURRING E OF 85W...INCLUDING PORTIONS OF THE FLORIDA STRAITS. OVERALL...THE SURFACE RIDGE ANCHORED LARGELY OVER THE SW NORTH ATLC WILL REMAINS IN PLACE ACROSS THE GULF THROUGH THE WEEKEND PROVIDING E-SE WINDS. BY SUNDAY...A WEAK FRONTAL BOUNDARY WILL APPROACH THE TEXAS AND LOUISIANA COAST AND SLOWLY SKIRT THE NORTHERN GULF COAST AND SE CONUS. CARIBBEAN SEA... MOST OF THE CARIBBEAN IS UNDER IN THE INFLUENCE OF UPPER LEVEL RIDGING WITH ONE ANTICYCLONE CENTERED OVER THE NW CARIBBEAN NEAR 18N87W AND THE OTHER ANTICYCLONE CENTERED OVER THE SE CARIBBEAN NEAR 11N65W. THIS RESULTS IN AN OVERALL DIFFLUENT ATMOSPHERIC ENVIRONMENT. COUPLED WITH SUSTAINED MOIST E-SE LOW-LEVEL FLOW ON THE SOUTHERN PERIPHERY OF A SURFACE RIDGE ANCHORED IN THE SW NORTH ATLC...AREAS OF CONVECTION PERSIST THIS EVENING. ONE SUCH AREA IS SCATTERED SHOWERS AND TSTMS FROM 14N-22N BETWEEN 76W- 82W. OTHERWISE...OTHER AREAS REMAIN AS ISOLATED SHOWERS AND TSTMS ACROSS PUERTO RICO AND HISPANIOLA...AS WELL AS THE SE CARIBBEAN S OF 14N E OF 65W. FINALLY...THE MONSOON TROUGH AXIS EXTENDS ALONG 12N FROM NORTHERN COLOMBIA TO NICARAGUA AND HONDURAS. WIDELY SCATTERED SHOWERS AND TSTMS ARE OCCURRING OVER THE AREA S OF 14N BETWEEN 73W-87W. THE OVERALL SYNOPTIC PATTERN OF E-SE TRADES IS EXPECTED TO PERSIST THROUGH EARLY NEXT WEEK AS HIGH PRESSURE REMAINS ANCHORED TO THE NORTH IN THE SW NORTH ATLC. HISPANIOLA... HISPANIOLA REMAINS UNDER THE INFLUENCE OF MIDDLE TO UPPER LEVEL DIFFLUENCE EAST OF A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH NOTED ON WATER VAPOR IMAGERY WITH AXIS ALONG 74W. THE DIFFLUENCE ALOFT COUPLED WITH PERSISTENT MOIST LOW-LEVEL SOUTHEASTERLY FLOW IS CONTINUING TO SUPPORT SCATTERED SHOWERS ACROSS THE ISLAND THIS EVENING. LOOKING AHEAD...AS THE UPPER LEVEL TROUGH SLOWLY PROGRESSES EASTWARD...LINGERING SUPPORTING DYNAMICS ALOFT WILL REMAIN OVER HISPANIOLA FRIDAY INTO SATURDAY WITH SCATTERED SHOWERS AND TSTMS EXPECTED...ESPECIALLY DURING THE AFTERNOON AND EVENING HOURS DUE TO PEAK DAYTIME HEATING AND INSTABILITY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW IS NOTED ON WATER VAPOR IMAGERY CENTERED NEAR 32N73W WITH AXIS EXTENDING SOUTHWARD TO 20N ALONG 73W. WHILE THIS UPPER LEVEL FEATURE IS FOUND LARGELY ABOVE SURFACE RIDGING ACROSS THE SW NORTH ATLC...LIFTING DYNAMICS CONTINUE TO PRODUCE EXTENSIVE CLOUDINESS WITH SCATTERED SHOWERS AND TSTMS ACROSS THE REGION FROM 18N-34N BETWEEN 65W-76W. OTHERWISE...THE SW NORTH ATLC REMAINS UNDER THE INFLUENCE OF A SURFACE RIDGE W OF 60W WITH SUSTAINED E-SE WINDS IN THE RANGE OF 10-20 KT. THIS OVERALL SYNOPTIC PATTERN IS EXPECTED TO PERSIST THROUGH EARLY SUNDAY. FARTHER EAST...BRIDGING THE PREVIOUSLY MENTIONED RIDGE AND A STRONGER SURFACE RIDGE OVER THE EASTERN ATLC...IS A FRONTAL TROUGH HIGHLIGHTED BY A STATIONARY FRONT ANALYZED FROM 33N45W TO 31N47W AND A SURFACE TROUGH ANALYZED FROM 31N52W TO 26N57W. ISOLATED SHOWERS ARE OCCURRING WITHIN 180 NM EITHER SIDE OF A LINE FROM 32N46W TO 26N57W. FINALLY...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC ARE UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1035 MB HIGH CENTERED N OF THE AZORES NEAR 41N26W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN