000 AXNT20 KNHC 300543 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON APR 30 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 09N13W TO 07N18W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N18W TO 03N35W TO THE EQUATOR NEAR 50W. SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 06N BETWEEN 25W-37W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH EXTENDS OVER THE EASTERN GULF FROM 28N85W SOUTH-SOUTHEASTWARD OVER THE FLORIDA STRAITS TO EASTERN CUBA NEAR 21N78W. WHILE MOST OF THE ACTIVE WEATHER ASSOCIATED WITH THIS TROUGH CONTINUES TO BE ACROSS THE FLORIDA PENINSULA AND IN THE SW NORTH ATLC...A FEW WIDELY SCATTERED SHOWERS ARE OCCURRING OVER THE FLORIDA STRAITS AND IN THE VICINITY OF THE FLORIDA KEYS S OF 26N E OF 84W. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF WEST-NORTHWESTERLY FLOW ALOFT WITH MOSTLY DRY AIR AND SUBSIDENCE NOTED ON WATER VAPOR IMAGERY BETWEEN 84W-90W. AT THE SURFACE...A WEAK SURFACE RIDGE AXIS EXTENDS FROM NORTHERN FLORIDA AND SOUTHERN GEORGIA NEAR 31N84W TO THE TEXAS GULF COAST NEAR 27N97W. EAST TO SOUTHEAST WINDS IN THE RANGE OF 10 TO 20 KT ARE EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS INTO LATE MONDAY AS A WEAK SURFACE TROUGH...ANALYZED OVER THE FLORIDA STRAITS AND NW CARIBBEAN SEA MOVES WEST-NORTHWESTWARD OVER THE NEXT 24 TO 36 HOURS INTO THE CENTRAL GULF. WHILE THE ECMWF... NAM...AND UKMET HAVE BEEN CONSISTENTLY SUGGESTING THIS WEAK TROUGHING TO DRIFT WESTWARD...THIS EVENING THE GFS HAS TRENDED LESS AGGRESSIVE WITH FORMING A SURFACE LOW OVER THE CENTRAL GULF ON MONDAY AND COME MORE INTO LINE WITH THE OTHER GLOBAL MODEL SOLUTIONS. THEREFORE...THE FORECAST CONTINUES TO INDICATE THIS TROUGHING WHICH IS EXPECTED TO DISSIPATE BY TUESDAY OVER THE NW GULF WATERS. CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE FLORIDA STRAITS THIS EVENING AND EXTENDS A TROUGH AXIS SOUTH-SOUTHEASTWARD TO EASTERN CUBA NEAR 21N78W. WATER VAPOR IMAGERY INDICATES A VERY DRY AIRMASS IS IN PLACE SOUTHWEST OF THIS UPPER LEVEL TROUGH AXIS AS WEST-NORTHWESTERLY FLOW ALOFT DOMINATES N OF 16N W OF 78W. HOWEVER...AS A RESULT OF THE UPPER LEVEL TROUGH...A WEAK SURFACE TROUGH IS ANALYZED FROM THE FLORIDA STRAITS NEAR 24N82W ACROSS WESTERN CUBA TO 18N83W. A FEW ISOLATED LOW-TOPPED SHOWERS ARE OCCURRING IN THE VICINITY OF THE SURFACE TROUGH AXIS N OF 17N BETWEEN 75W-84W...INCLUDING JAMAICA AND MUCH OF CUBA. THIS SURFACE TROUGH IS EXPECTED TO DRIFT WEST-NORTHWESTWARD OVER THE NEXT 24 TO 36 HOURS INTO THE CENTRAL GULF OF MEXICO. THE REMAINDER OF THE CARIBBEAN FALLS UNDER THE INFLUENCE OF SOUTHWEST TO WESTERLY UPPER LEVEL FLOW DUE TO AN ANTICYCLONIC CIRCULATION CENTERED OVER NORTH-CENTRAL VENEZUELA NEAR 10N66W. MOST OF THE MIDDLE TO UPPER LEVEL MOISTURE ASSOCIATED WITH THIS RIDGE IS LOCATED ON THE NORTHWESTERN PERIPHERY THAT CONTINUES TO PROVIDE HIGH LEVEL CLOUDINESS E OF 75W. AT THE SURFACE... MODERATE TO FRESH EASTERLIES ARE NOTED ON RECENT OBSERVATIONS AND ASCAT SCATTEROMETER PASSES WHICH ARE FORECAST TO PERSIST THROUGH WEDNESDAY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW AND ASSOCIATED TROUGH IS CENTERED OVER THE FLORIDA STRAITS AND IS PROVIDING MOST OF THE SW NORTH ATLC WITH PLENTY OF MOISTURE AND OVERCAST CLOUDINESS W OF 60W. INFRARED SATELLITE IMAGERY INDICATES THAT SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER A LARGE AREA FROM 20N-30N BETWEEN 60W-81W. THE RIDGE AXIS OVER NORTHERN FLORIDA AND THE SW NORTH ATLC PRESENT YESTERDAY HAS SLOWLY ERODED AND SHIFTED EASTWARD AS A WEAK STATIONARY FRONT REMAINS ANALYZED TO THE NORTH OF THE DISCUSSION AREA ALONG 33N BETWEEN 70W AND THE SOUTH CAROLINA COAST. OTHERWISE...THE SW NORTH ATLC CONTINUES TO EXPERIENCE E-SE WINDS IN THE RANGE OF 10 TO 20 KT WITH POSSIBLE STRONGER WINDS S OF 27N W OF 70W DUE TO THE CLOSE PROXIMITY OF THE SURFACE TROUGH ACROSS THE FLORIDA STRAITS. FARTHER EAST...AN UPPER LEVEL LOW IS CENTERED NEAR 27N41W AND CONTINUES TO PROVIDE SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW WITH MOISTURE STREAMING NORTHEASTWARD FROM THE TROPICS TO THE NORTHEAST AFRICAN COAST. AT THE SURFACE HOWEVER...A SURFACE RIDGE HOLDS STRONG ANCHORED BY A 1032 MB HIGH CENTERED NW OF THE AZORES NEAR 40N33W. FRESH TO STRONG NE WINDS WERE NOTED ON EARLIER ASCAT PASSES OFF THE COAST OF WESTERN SAHARA STRETCHING TO THE NORTHERN CAPE VERDE ISLANDS TO 15N30W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN