000 AXNT20 KNHC 241124 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN MAY 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 50W S OF 10N MOVING W NEAR 18 KT. THIS WAVE IS ASSOCIATED WITH A MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SATELLITE IMAGERY INDICATES THAT THE WAVE IS EMBEDDED WITHIN AN INVERTED-V CLOUD SIGNATURE...WITH CYCLONIC CIRCULATION IN THE MOTION OF THE LOW LEVEL CLOUDS IN THE VICINITY OF THE WAVE AXIS. SCATTERED MODERATE CONVECTION IS WITHIN 300 NM E OF THE WAVE AXIS S OF 4N. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 6N10W 4N17W 2N26W CROSSING THE EQUATOR NEAR 33W EXTENDING JUST S OF THE EQUATOR TO THE COAST OF NE BRAZIL NEAR 1S47W. SCATTERED MODERATE CONVECTION IS WITHIN 50 NM OF A LINE FROM 3N4W TO 1N12W. SIMILAR CONVECTION IS ALSO S OF 3N BETWEEN 35W-49W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYER TROUGH IS PRESENT ACROSS THE GULF WITH AN AXIS EXTENDING FROM AN UPPER LOW OVER LOUISIANA NEAR 31N93W TO THE ERN STRAITS OF FLORIDA NEAR 24N80W. AN ASSOCIATED 1006 MB SURFACE LOW IS LOCATED INLAND ACROSS CENTRAL MISSISSIPPI NEAR 33N90W...WITH A SURFACE TROUGH EXTENDING FROM THE LOW ACROSS THE EXTREME WRN FLORIDA PANHANDLE INTO THE GULF NEAR 30N87W EXTENDING TO 24N89W. LOW LEVEL CONVERGENCE ALONG THE SURFACE TROUGH...AS WELL AS UPPER LEVEL DIFFLUENCE NE OF THE UPPER TROUGH AXIS...ARE SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS THE NE GULF NE OF A LINE FROM WRN CUBA NEAR 23N83W TO GULFPORT MISSISSIPPI NEAR 30N89W. UPPER DIFFLUENCE NEAR THE BASE OF THE UPPER TROUGH IS GENERATING SCATTERED SHOWERS AND TSTMS ACROSS THE FLORIDA STRAITS E OF 81W. AS THE SURFACE LOW CONTINUES MOVING N-NW MAINLY LIGHT SOUTHERLY SURFACE FLOW WILL PREVAIL ACROSS THE ENTIRE GULF THROUGH TUES AND GRADUALLY INCREASE AS THE NEXT AREA OF LOW PRESSURE DEVELOPS ACROSS THE SRN PLAIN STATES. ACROSS THE SW GULF...DEEP LAYER DRY AIR AND SUBSIDENCE ASSOCIATED WITH W-NW FLOW ALOFT AND A WEAK 1014 MB SURFACE HIGH CENTERED NEAR 24N93W IS SUPPORTING GENERALLY FAIR WEATHER CONDITIONS. CARIBBEAN SEA... SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING ACROSS THE CARIBBEAN N OF 17N E OF 80W AND THE ADJACENT COASTAL WATERS ALONG THE SRN COAST OF CUBA. THIS ACTIVITY IS BEING SUPPORTED BY UPPER LEVEL DIFFLUENCE IN MOIST WESTERLY FLOW ALOFT BETWEEN AN UPPER LEVEL TROUGH EXTENDING FROM THE GULF OF MEXICO TO OVER THE NW CARIBBEAN...AND AN UPPER LEVEL RIDGE ACROSS THE SW NORTH ATLC. THIS SYNOPTIC PATTERN HAS PERSISTED FOR THE PAST FEW DAYS AND IS RESULTING IN CONTINUED PRECIPITATION ACROSS CUBA... JAMAICA...HISPANIOLA...PUERTO RICO AND THE NEARBY COASTAL WATERS ACROSS THE NRN CARIBBEAN. THE UPPER TROUGH IS FORECAST TO DRIFT SLOWLY EWD AND BEGIN WEAKENING BY LATE MONDAY. ADDITIONAL SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING ACROSS CENTRAL AMERICA AND THE SW CARIBBEAN WATERS SW OF A LINE FROM 18N88W TO 11N75W. INCLUDED IN THIS AREA IS A 1009 MB COLOMBIA SURFACE LOW AND THE EWD EXTENSION OF THE E PACIFIC ITCZ AXIS ACROSS PANAMA. THIS ACTIVITY IS ALSO BEING SUPPORTING BY UPPER LEVEL DIFFLUENCE ON THE EXTENSION OF AN UPPER LEVEL RIDGE FROM THE E PACIFIC REGION EWD TO 65W. MEANWHILE...THE SURFACE PRESSURE GRADIENT S OF A SURFACE RIDGE OVER THE W ATLC IS MAINTAINING ELY TRADES OF 20 TO 25 KT ACROSS PORTIONS OF THE ERN CARIBBEAN. ATLANTIC OCEAN... SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING SW OF A LINE FROM 32N81W NEAR THE SRN SOUTH CAROLINA COAST TO N OF THE LEEWARD ISLANDS NEAR 20N61W. THIS AREA INCLUDES THE BAHAMAS... TURKS AND CAICOS ISLANDS...GREATER ANTILLES AND ADJACENT NEARBY COASTAL WATERS ALONG THE ERN FLORIDA PENINSULA. THIS ACTIVITY IS BEING SUPPORTED BY UPPER LEVEL DIFFLUENCE IN MOIST SWLY FLOW ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO AND AN UPPER LEVEL RIDGE OVER THE SW NORTH ATLC. FARTHER TO THE E... AN UPPER LEVEL TROUGH IS PRESENT WITH AN AXIS EXTENDING FROM AN UPPER LEVEL LOW NEAR 33N46W TO 26N55W TO 24N61W. ATMOSPHERIC INSTABILITY NEAR THE UPPER LEVEL LOW AND TROUGH...AS WELL AS UPPER LEVEL DIFFLUENCE IN MOIST SWLY FLOW ALOFT...ARE SUPPORTING SCATTERED MODERATE CONVECTION N OF 28N BETWEEN 36W-47W. ALSO...A SURFACE TROUGH EXTENDS FROM A 1018 MB SURFACE LOW NEAR 32N46W SW ALONG 28N49W INTO A 1017 MB LOW NEAR 25N52W AND CONTINUING ALONG 23N55W TO N OF THE LEEWARD ISLANDS NEAR 19N62W. LOW LEVEL CONVERGENCE NEAR THE SURFACE LOWS AND SURFACE TROUGH AXIS IS SUPPORTING SCATTERED SHOWERS WITHIN 300 NM E OF THE TROUGH AXIS. ACROSS THE E ATLC...A SURFACE RIDGE IS PRESENT WHERE MAINLY ZONAL FLOW ALOFT IS OCCURRING AND FAIR WEATHER CONDITIONS PERSIST. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS S OF 6N E OF 55W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THE UPPER LEVEL RIDGE IS ENHANCING CONVECTION ASSOCIATED WITH THE ITCZ AND THE TROPICAL WAVE ALONG 50W. $$ HUFFMAN