000 AXNT20 KNHC 241741 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI APR 24 2009 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N9W 3N15W CROSSING THE EQUATOR NEAR 21W CONTINUING ALONG 1S30W AND INTO NE BRAZIL NEAR 3S40W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 220 NM EITHER SIDE OF THE AXIS BETWEEN 11W-25W. ISOLATED MODERATE CONVECTION IS S OF 2N W OF 40W. ...DISCUSSION... GULF OF MEXICO... SURFACE HIGH PRESSURE IS CENTERED OVER THE W ATLC AND EXTENDS RIDGING OVER THE NE WATERS PROVIDING LIGHT AND VARIABLE SURFACE FLOW N OF 26N E OF 89W. HOWEVER...SE WINDS HAVE INCREASED TO 20-25 KT ACROSS THE REMAINDER OF THE GULF DUE TO THE TIGHT PRESSURE GRADIENT BETWEEN THE W ATLC HIGH AND BROAD SURFACE TROUGHING OVER N CENTRAL MEXICO. THIS STRONG FLOW IS ELEVATING SEAS TO 8 FT OVER THE WRN WATERS AND WILL LIKELY INCREASE A FEW MORE FT OVER THE NEXT DAY OR TWO AS WINDS REMAIN STRONG. DRY AIR AND ZONAL FLOW IN THE MID AND UPPER LEVELS IS SUPPORTING THE FAIR WEATHER OBSERVED ACROSS THE REGION THIS AFTERNOON. A SHORTWAVE TROUGH CURRENTLY OVER CENTRAL TEXAS IS EXPECTED TO TRACK EWD ALONG THE TEXAS/LOUISIANA COAST LATE TODAY AND SAT... BRINGING AN INCREASE IN LOW AND MIDDLE LEVEL MOISTURE TO THE NW PORTION OF THE GULF. CARIBBEAN SEA... ISOLATED WESTWARD MOVING SHOWERS LIE OVER A LARGE PORTION OF THE CARIBBEAN AS LOW-LEVEL LIFT FROM TRADE WIND CONVERGENCE AND MOIST ZONAL FLOW UNDER DIFFLUENCE ALOFT APPEAR TO BE THE PRIMARY MECHANISMS. THE STRONG UPPER LEVEL SWLY FLOW ON THE NRN PERIPHERY OF AN UPPER ANTICYCLONE CENTERED OVER VENEZUELA NEAR 5N66W IS SPREADING MOISTURE NE IN THE FORM OF MID-HIGH LEVEL CLOUDINESS W OF 70W. TRADE WINDS ARE IN THE 25-30 KT RANGE NEAR THE COAST OF COLOMBIA...AND MAINLY 20-25 KT ELSEWHERE. LITTLE CHANGE IN THIS WIND REGIME IS EXPECTED THROUGH THE WEEKEND AS STRONG HIGH PRESSURE REMAINS OVER THE W ATLC. ATLANTIC OCEAN... A LONGWAVE UPPER TROUGH CONTINUES TO PROVIDE SUPPORT FOR A COLD FRONTAL BOUNDARY EXTENDING FROM 32N59W TO 29N62W THEN STATIONARY SW TO THE WINDWARD PASSAGE. MULTILAYER CLOUDINESS WITH EMBEDDED SCATTERED SHOWERS ARE WITHIN 300 NM E OF THE COLD FRONT AND WITHIN 120 NM EITHER SIDE OF THE STATIONARY PORTION. A REINFORCING FRONT IS APPROACHING THE AREA JUST SE OF BERMUDA. THIS BOUNDARY WILL LIKELY MERGE WITH THE LEADING FRONT OVER THE NEXT 24 HOURS AS MID-LEVEL ENERGY PUSHES SEWD AND BEGINS TO FURTHER DISPLACE THE SURFACE FRONT TO THE EAST. A 1028 MB SURFACE HIGH PRESSURE IS ESTABLISHED BEHIND THE FRONT NEAR 34N71W. THIS HIGH PRESSURE IS EXPECTED TO STRENGTHEN OVER THE NEXT COUPLE OF DAYS IN THE W ATLC SETTING UP STRONG ELY FLOW ON ITS SRN PERIPHERY. FARTHER E...A MID-UPPER LOW IS SITUATED NEAR 27N32W WITH TROUGHING EXTENDING WELL SW ALONG 14N45W 2N45W. INSTABILITY ASSOCIATED WITH UPPER CYCLONE IS PRODUCING SCATTERED SHOWERS FROM 23N-31N BETWEEN 25W-36W. AN UPPER JET ORIGINATES NEAR THE BASE OF THE UPPER TROUGH AND EXTENDS NE FROM NORTH OF THE CAPE VERDE ISLANDS TO NEAR THE CANARY ISLANDS. THIS FLOW IS ADVECTING TROPICAL MOISTURE WELL NE INLAND ACROSS WESTERN SAHARA AND MAURITANIA OVER W AFRICA. $$ HUFFMAN