000 AXNT20 KNHC 030551 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU MAY 03 2012 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 09N14W TO TO 06N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N20W TO 02N34W TO 01N50W. SCATTERED MODERATE CONVECTION IS FROM 02N-06N BETWEEN THE PRIME MERIDIAN AND 03W...AND FROM 03N-08N BETWEEN 11W-17W. ISOLATED MODERATE CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 31W-39W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL SHORTWAVE TROUGH IS PROGRESSING EAST- NORTHEASTWARD OVER THE GULF COASTAL PLAINS THIS EVENING WITH AXIS EXTENDING INTO THE NE GULF ALONG 30N90W TO 26N87W. WHILE VERY WEAK SURFACE TROUGHING IS ACROSS THE EASTERN GULF IN ASSOCIATION WITH THIS MIDDLE TO UPPER LEVEL FEATURE...MOSAIC DOPPLER RADAR AND LIGHTNING DATA INDICATE SCATTERED SHOWERS AND TSTMS ARE OCCURRING N OF 26N BETWEEN 83W-89W...INCLUDING THE NEAR COASTAL ZONES IMMEDIATELY E OF THE MISSISSIPPI RIVER DELTA REGION. LOW-LEVEL MOISTURE IS PREVALENT SE OF THIS CONVECTIVE ACTIVITY OVER THE SE GULF WITH ISOLATED SHOWERS OCCURRING S OF 26N BETWEEN 82W-87W. OTHERWISE...THE REMAINDER OF THE GULF BASIN IS UNDER THE INFLUENCE OF STABLE NW FLOW ALOFT DUE TO AN UPPER LEVEL RIDGE WITH AXIS ALONG 97W. HIGH LEVEL MOISTURE AND CLOUDINESS CONTINUES TO SPILL OVER THE TOP OF THE RIDGE W OF 92W...WITH MOSTLY LIGHT EAST TO SOUTHEAST WINDS OBSERVED IN THE RANGE OF 10 TO 15 KT W OF 90W. HIGH PRESSURE IS FORECAST TO ANCHOR ITSELF OVER THE FLORIDA PENINSULA FRIDAY INTO THE WEEKEND AND GRADUALLY SLIDE WESTWARD INTO THE EASTERN GULF BY MONDAY. CARIBBEAN SEA... WESTERLY UPPER LEVEL FLOW DOMINATES ACROSS THE CARIBBEAN THIS EVENING WITH MOST MIDDLE TO UPPER LEVEL MOISTURE REMAINING E OF 75W. LOW-LEVEL MOISTURE IS PRESENT OVER TWO NOTABLE AREAS OF THE CARIBBEAN. THE FIRST AREA IS LOW-LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH THE EXTENSION OF MIDDLE TO UPPER LEVEL TROUGHING ACROSS THE EASTERN GULF OF MEXICO SOUTHEASTWARD OVER PORTIONS OF CUBA. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING N OF 19N BETWEEN 75W-85W. THIS ACTIVITY HOWEVER CONTINUES ON A DIMINISHING TREND OVER THE PAST 6 HOURS DUE TO THE LOSS OF PEAK DAYTIME HEATING AND INSTABILITY. FARTHER EAST...THE OTHER AREA OF LOW-LEVEL MOISTURE IS ASSOCIATED WITH VERY WEAK AND SUBTLE TROUGHING ACROSS THE EASTERN CARIBBEAN EMBEDDED WITHIN THE EASTERLY TRADE FLOW. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER THE NE CARIBBEAN N OF 15N E OF 72W... INCLUDING PUERTO RICO AND THE LEEWARD ISLANDS. OTHERWISE... MODERATE TO FRESH EASTERLY TRADES ARE EXPECTED TO PERSIST THROUGH FRIDAY THEN BEGIN TO GRADUALLY DIMINISH THROUGH THE WEEKEND. ATLANTIC OCEAN... MIDDLE TO UPPER LEVEL RIDGING IS ANCHORED ACROSS THE SW NORTH ATLC AND THIS MANIFESTS ITSELF AT THE SURFACE WITH A 1022 MB HIGH CENTERED NEAR 30N72W. CLEAR SKIES ARE NOTED OVER THE REGION N OF 20N W OF 60W. FARTHER EAST...BROAD UPPER LEVEL TROUGHING IS IMPACTING THE CENTRAL ATLC WATERS THAT IS RESULTING IN A WEAKNESS BETWEEN THE TWO SUBTROPICAL RIDGES. A SURFACE TROUGH IS ANALYZED FROM 29N45W SW TO 24N55W AND IS PROVIDING FOCUS FOR WIDELY SCATTERED SHOWERS OVER A LARGE AREA FROM 20N-30N BETWEEN 43W-60W. THIS MOISTURE EXTENDS SOUTHWEST TOWARDS THE NE CARIBBEAN SEA REGION WITH STRONGER CONVECTION OCCURRING S OF 20N BETWEEN 55W-70W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED NEAR 27N27W. OF NOTE...EXAMINING EARLIER VISIBLE METEOSAT-9 SATELLITE IMAGERY AND THE CURRENT CIMSS SAHARAN AIR LAYER TRACKING PRODUCT...A LARGE AREA OF DUST IS OBSERVED EXTENDING OFF THE WESTERN COAST OF AFRICA. THE SUSPENDED DUST IS MOST CONCENTRATED WITHIN 150 NM EITHER SIDE OF A LINE FROM 20N16W TO 14N30W...INCLUDING THE CAPE VERDE ISLANDS...AND ENCOMPASSES A LARGER OVERALL AREA ACROSS THE EASTERN TROPICAL ATLC FROM 10N-23N E OF 40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN