000 AXNT20 KNHC 061748 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED APR 06 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ... ITCZ AXIS IS ALONG 06N10W 02N22W CROSSING THE EQUATOR NEAR 39W THEN INTO NE BRAZIL NEAR 02S44W. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 11W-23W. ...DISCUSSION... GULF OF MEXICO... AS OF 06/1500 UTC...WATER VAPOR IMAGERY INDICATES A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH ACROSS THE SOUTH CENTRAL GULF THAT SUPPORTS A WEAK 1016 MB LOW CENTERED NORTH OF THE YUCATAN PENINSULA NEAR 23N89W. LATEST VISIBLE SATELLITE IMAGERY SHOWS A DISSIPATING STATIONARY FRONT DRAPED ACROSS THE STRAITS OF FLORIDA AND NORTHERN COAST OF CUBA TO 23N85W WHERE THE BOUNDARY CONTINUES WESTWARD AS A STATIONARY FRONT INTO THE LOW CENTER. THE FRONT ALSO EXTENDS SW FROM THE LOW TO THE MEXICO COAST NEAR CIUDAD DEL CARMEN. ISOLATED SHOWERS ARE PRIMARILY OCCURRING NE OF THE LOW CENTER ACROSS THE SE GULF FROM 23N-26N BETWEEN 85W-90W. THE FRONT IS EXPECTED TO CONTINUE A WEAKENING TREND OVER THE NEXT 24 TO 36 HOURS AS RIDGING BUILDS IN ACROSS THE ENTIRE BASIN BY EARLY THURSDAY WITH SE RETURN FLOW IN THE RANGE OF 10 TO 20 KT...STRONGEST W OF 90W. CARIBBEAN SEA... THE CARIBBEAN SEA REMAINS UNDER MOSTLY SOUTHWESTERLY UPPER LEVEL FLOW BETWEEN UPPER LEVEL TROUGHING OVER THE GULF OF MEXICO AND AN ANTICYCLONIC CIRCULATION CENTERED OVER THE SE CARIBBEAN NEAR 12N68W PROVIDING MOSTLY DRY AIR AND SUBSIDENCE OVER MUCH OF THE EASTERN CARIBBEAN E OF 70W. WATER VAPOR IMAGERY INDICATES A STREAM OF MIDDLE TO UPPER LEVEL MOISTURE ON THE WESTERN PERIPHERY OF THE RIDGE EXTENDING FROM PANAMA ACROSS JAMAICA AND EASTERN CUBA THAT CONNECTS UP WITH AN UPPER LEVEL SHORTWAVE TROUGH PROGRESSING ACROSS THE W ATLC ALONG 68W. AT THE SURFACE...EASTERLY TRADES CONTINUE AND ARE EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE WEEK DUE TO A STATIONARY RIDGE LOCATED IN THE SW NORTH ATLC. LOW-LEVEL MOISTURE CONTINUES TO ADVECT WESTWARD ACROSS THE BASIN WITH ISOLATED SHOWERS OCCURRING OVER EASTERN HISPANIOLA FROM 17N-20N BETWEEN 68W-71W...AND IN THE SW CARIBBEAN S OF 12N. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS SWEEPING ACROSS THE W ATLC WATERS WITH TROUGH AXIS ALONG 68W THAT DIPS SOUTHWARD TO 28N. THE THOUGH SUPPORTS A COLD FRONT ANALYZED INTO THE REGION NEAR 32N67W THAT EXTENDS SW TO THE NW AND CENTRAL BAHAMAS NEAR 26N77W THAT CONTINUES WESTWARD THROUGH THE STRAITS OF FLORIDA AND INTO THE SE GULF OF MEXICO. WHILE MUCH LESS CONVECTIVELY ACTIVE TODAY THAN YESTERDAY...ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EAST OF THE FRONT N OF 26N. THE COLD FRONT IS FORECAST TO PROGRESS E-NE OVER THE NEXT 24 HOURS WITH MOST ACTIVE CONVECTION REMAINING IN THE VICINITY OF THE FRONT AND N OF 25N. A 1024 MB HIGH IS EXPECTED TO CONTINUE BUILDING IN BEHIND THE FRONT AND CURRENTLY IS PROVIDING FOR MOSTLY FAIR WEATHER AND CLEAR SKIES OVER MUCH OF THE SW NORTH ATLC N OF 27N W OF 72W. FARTHER EAST...AN AMPLIFIED UPPER LEVEL TROUGH IS ALONG 28W WITH AN AXIS THROUGH 32N28W 24N31W TO A BASE NEAR 20N40W. THIS UPPER LEVEL TROUGH SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N24W AND EXTENDS SW TO 24N33W...THEN BECOMES A SHEAR LINE W-SW TO 20N52W. A RECENT 06/1316 UTC ASCAT PASS DEPICTED STRONGER NE WINDS OF 20 KT WITHIN 120 NM NORTH OF THE BOUNDARY BETWEEN 42W-54W. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF THE SUBTROPICAL RIDGE ANCHORED BY A 1030 MB HIGH CENTERED NEAR 36N46W N OF THE AFOREMENTIONED SHEAR LINE AND A 1017 MB HIGH CENTERED OVER THE CANARY ISLANDS NEAR 29N13W EAST OF THE COLD FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN