000 AXNT20 KNHC 071743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT MAY 07 2011 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ... ITCZ AXIS IS ALONG 09N13W 03N25W 01N35W 03N51W. SCATTERED MODERATE CONVECTION IS WITHIN 150 NM EITHER SIDE OF A LINE FROM 01N06W TO 07N15W. ISOLATED MODERATE CONVECTION IS FROM 02N-05N BETWEEN 23W-26W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES STRONG WESTERLY ZONAL FLOW IS LOCATED ALOFT OVER THE GULF THIS AFTERNOON WHICH IS PROMOTING MOSTLY FAIR WEATHER ACROSS THE BASIN. A DISSIPATING AND FAIRLY DIFFUSE FRONTAL BOUNDARY IS DRAPED ACROSS THE SOUTHERN FLORIDA PENINSULA FROM WEST PALM BEACH TO FORT MYERS THAT EXTENDS WESTWARD INTO THE SE GULF NEAR 26N87W. VISIBLE SATELLITE IMAGERY SHOWS THAT ISOLATED SHOWERS ARE POSSIBLE WITHIN 30 NM EITHER SIDE OF THE BOUNDARY. NORTH OF THE FRONT AT 07/1500 UTC...A 1019 MB HIGH IS CENTERED OVER THE NE GULF NEAR 29N84W AND EXTENDS A RIDGE AXIS SW TO THE COAST OF EAST-CENTRAL MEXICO NEAR 21N97W. E TO SE WINDS FLOW AROUND THE SURFACE RIDGE AND THIS OVERALL PATTERN IS FORECAST TO PERSIST THROUGH THE REMAINDER OF THE WEEKEND AS WELL AS MUCH OF NEXT WEEK. THE SURFACE HIGH CONTINUES STATIONARY OVER THE NE GULF THROUGH NEXT WEEK WITH SOUTHERLY FLOW UP TO 20 KT EXPECTED OVER THE WESTERN GULF W OF 90W. CARIBBEAN SEA... MUCH OF THE CARIBBEAN SEA BASIN IS UNDER THE INFLUENCE OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 16N76W. WATER VAPOR IMAGERY INDICATES DRY AIR AND SUBSIDENCE FROM 16N-21N BETWEEN 60W-90W IN ASSOCIATION WITH THE UPPER LEVEL FEATURE. THIS IS RESULTING IN MOSTLY CLEAR SKIES AND FAIR CONDITIONS THIS AFTERNOON ALTHOUGH A FEW LOW-TOPPED ISOLATED SHOWERS ARE OCCURRING IN THE VICINITY OF EASTERN JAMAICA AND SOUTHWESTERN HISPANIOLA. FARTHER EAST...TOTAL PRECIPITABLE WATER IMAGERY SHOWS INCREASED VALUES OF LOW-LEVEL MOISTURE ADVECTING ACROSS THE LESSER ANTILLES THIS AFTERNOON. THIS EAST-WEST BAND OF MOISTURE...MOST LIKELY REMNANT FRONTAL MOISTURE IS GENERATING WIDELY SCATTERED SHOWERS WITHIN 120 NM EITHER SIDE OF A LINE FROM 16N58W TO 14N70W. ELSEWHERE...EASTERLY TRADES CONTINUE ACROSS THE BASIN S OF 18N IN THE RANGE OF 10 TO 20 KT WITH LOW-LEVEL CONVERGENCE OF THESE TRADES OCCURRING ACROSS THE SW CARIBBEAN. ISOLATED TO WIDELY SCATTERED SHOWERS WILL CONTINUE TO MOVE ONSHORE ACROSS WESTERN PANAMA...COSTA RICA...AND NICARAGUA THROUGH THE EVENING HOURS. ATLANTIC OCEAN... AN UPPER LEVEL SHORTWAVE IS LOCATED OFF THE CAROLINA COAST AND EXTENDS A COLD FRONT INTO THE SW NORTH ATLC NEAR 32N74W THEN SW ALONG 29N76W AND TO THE FLORIDA COAST NEAR WEST PALM BEACH. MOSTLY ZONAL UPPER LEVEL FLOW IS LOCATED S OF 30N AND THE FRONT CONTINUES TO BECOME MORE DIFFUSE AS THE UPPER LEVEL ENERGY MOVES NE OF THE AREA. HOWEVER...ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN 45 NM E OF THE FRONT AND N OF 28N BETWEEN 70W AND THE FRONT. THIS SYSTEM IS FORECAST TO MOVE E-NE OVER THE NEXT 24 TO 36 HOURS AS HIGH PRESSURE BUILDS EASTWARD FROM THE NE GULF OF MEXICO. THE REMAINDER OF THE SW NORTH ATLC IS UNDER A VERY WEAK HIGH PRESSURE REGIME BETWEEN 58W-80W SE OF THE AFOREMENTIONED COLD FRONT. A FEW ISOLATED SHOWERS CONTINUE TO ADVECT WESTWARD ACROSS THE TURKS AND CAICOS ISLANDS AS WELL AS THE SE BAHAMAS THIS AFTERNOON. ACROSS THE CENTRAL ATLC...A COMPLEX 1009 MB LOW IS CENTERED NEAR 31N48W. SEVERAL WAVES OF ENERGY CONTINUE TO ROTATE AROUND THE MEAN LOW AND THESE ARE ANALYZED AS SURFACE TROUGH BOUNDARIES. WHILE MOST OF THE ACTIVE WEATHER ASSOCIATED WITH THE LOW IS LOCATED N OF 32N...THE LEADING AND MOST SUBSTANTIAL SURFACE TROUGH IS ALONG 32N39W 26N40W 20N44W TO 16N52W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 120 NM OF THE TROUGH AXIS S OF 22N WHILE WIDELY SCATTERED SHOWERS COVER THE AREA FROM 22N-32N BETWEEN 31W-40W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NW OF THE CANARY ISLANDS NEAR 32N21W. THE SURFACE RIDGE AXIS EXTENDS SW FROM THE HIGH CENTER TO 17N40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN