000 AXNT20 KNHC 280552 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE MAY 28 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 12N16W TO 07N25W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N25W TO 05N40W TO 04N52W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 05N-10N BETWEEN 14W-20W. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 23W- 47W...AND FROM 01N-03N BETWEEN 41W-45W. ...DISCUSSION... GULF OF MEXICO... A WEAK UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE WESTERN GULF WITH AXIS EXTENDING FROM 29N89W S-SW TO A BASE OVER SOUTHERN MEXICO NEAR 17N96W. MOSTLY DRY AIR AND SUBSIDENCE IS LOCATED WEST OF THE TROUGH AXIS UNDER NORTHWESTERLY FLOW ALOFT PROVIDING FOR OVERALL CLEAR SKIES EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS INTO TUESDAY. EAST OF THE TROUGH AXIS...MIDDLE TO UPPER LEVEL DIFFLUENCE CONTINUES TO LIFT MOISTURE AND ADVECT IT NORTHEAST OVER THE SE GULF AND PORTIONS OF THE FLORIDA STRAITS AND NW CARIBBEAN SEA. SCATTERED SHOWERS AND WIDELY SCATTERED TSTMS ARE OCCURRING SOUTH OF 26N EAST OF 93W...INCLUDING THE FLORIDA STRAITS EASTWARD INTO THE SW NORTH ATLC. OTHERWISE...A SURFACE RIDGE IS PROVIDING FAIR CONDITIONS OVER THE NORTHERN GULF WITH AXIS EXTENDING WESTWARD FROM THE SW NORTH ATLC OFFSHORE OF THE CAROLINAS NEAR 34N70W TO 27N97W. E-SE WINDS PREVAIL IN THE RANGE OF 10 TO 20 KT WITH STRONGER WINDS POSSIBLE FILTERING THROUGH THE FLORIDA STRAITS AND AREAS S OF 26N BETWEEN 78W-84W. THE RIDGING IS EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE WEEK. CARIBBEAN SEA... UPPER LEVEL TROUGHING OVER THE CENTRAL CARIBBEAN IS LOCATED BETWEEN 60W-72W WITH AXIS ALONG 68W. TWO ANTICYCLONIC CIRCULATIONS ARE FOUND ON EITHER SIDE OF THE TROUGHING. WEST- NORTHWESTERLY FLOW IS NOTED W OF 68W WITH WATER VAPOR INDICATING AN AREA OF OVERALL DRY AND STABLE CONDITIONS FROM 11N-17N BETWEEN 70W-80W. CLOUDINESS AND MOISTURE INCREASE W OF 80W ESPECIALLY OVER THE NW CARIBBEAN WHERE MIDDLE TO UPPER LEVEL DIFFLUENCE IS MAXIMIZED. THIS ENVIRONMENT CONTINUES TO PRODUCE SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE NW CARIBBEAN... PORTIONS OF CUBA...AND MUCH OF CENTRAL AMERICA INCLUDING THE YUCATAN PENINSULA. EAST OF 68W...MOIST SOUTHWESTERLY FLOW CONTINUES TO AID IN GENERATING SCATTERED SHOWERS AND TSTMS EAST OF 70W WITH THE INCLUSION OF HISPANIOLA AND THE SURROUNDING ADJACENT COASTAL WATERS N OF 17N. E-SE TRADES ARE EXPECTED TO PERSIST THROUGH FRIDAY AS THE OVERALL SYNOPTIC PATTERN CHANGES LITTLE OVER THE NEXT FEW DAYS. HISPANIOLA... CURRENTLY WIDELY SCATTERED SHOWERS AND TSTMS ARE NOTED ON SATELLITE IMAGERY ACROSS THE ISLAND AND ADJACENT COAST WATERS. UPPER LEVEL TROUGHING STILL REMAINS OVER HISPANIOLA AND THIS AGAIN WILL PROVIDE FOR AN OVERALL UNSTABLE ENVIRONMENT TUESDAY AFTERNOON INTO THE EVENING HOURS. SCATTERED SHOWERS AND TSTMS ARE EXPECTED TO INITIATE DUE TO PEAK DAYTIME HEATING AND INSTABILITY WITH LOCALIZED FLOODING POSSIBLE WITH ANY CONVECTION THAT REMAINS OVER A SINGLE LOCALE FOR AN EXTENDED PERIOD OF TIME. ATLANTIC OCEAN... WESTERLY UPPER LEVEL FLOW IS INDICATED ON WATER VAPOR IMAGERY THIS EVENING OVER A LARGE PORTION OF THE SW NORTH ATLC AND THIS CONTINUES TO SUPPORT A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NEAR 34N70W. ON THE SOUTHERN PERIPHERY OF THIS RIDGING HOWEVER MOISTURE INCREASES DUE TO MIDDLE TO UPPER LEVEL DIFFLUENCE WITH SCATTERED SHOWERES AND TSTMS OCCURRING SOUTH OF 26N WEST OF 67W...AND SOUTH OF 21N WEST OF 52W. BRIDGING THIS SURFACE RIDGE AND A MORE DOMINATE RIDGE OVER THE CENTRAL AND EASTERN ATLC IS A STATIONARY FRONT ANALYZED FROM 32N61W TO 29N64W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...THE PREVIOUSLY MENTIONED SURFACE RIDGE OVER THE CENTRAL AND EASTERN ATLC DOMINATES A LARGE AREA ANCHORED BY A 1035 MB HIGH CENTERED NW OF THE AZORES NEAR 41N34W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN