000 AXNT20 KNHC 041132 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI NOV 04 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 08N58W TO 19N53W MOVING W AT 10-15 KT. THE WAVE REMAINS EMBEDDED WITHIN DEEP LAYER TROPICAL MOISTURE ACROSS THE WESTERN TROPICAL ATLC WITH CYCLONIC TURNING OF THE LOW-LEVEL CLOUD FIELD IN THE VICINITY OF THE WAVE AXIS BETWEEN 53W-60W. AS THE WAVE MOVES BENEATH UPPER LEVEL SOUTHWESTERLY SHEAR...ISOLATED MODERATE CONVECTION IS LIMITED TO 11N-14N BETWEEN 53W-55W...AND FROM 09N-11N BETWEEN 57W-61W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W TO 09N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 09N20W TO 06N26W TO 07N44W. ISOLATED MODERATE CONVECTION IS FROM 03N-05N BETWEEN 13W-31W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL TROUGH IS PROGRESSING EASTWARD ACROSS THE SE CONUS THAT SUPPORTS A COLD FRONT ANALYZED AT 04/0900 UTC FROM WACCASASSA BAY FLORIDA NEAR 30N85W SW TO 22N94W THEN SOUTHWARD TO THE MEXICO COAST NEAR COATZACOALCOS. THE MIDDLE TO UPPER LEVELS OF THE ATMOSPHERE REMAIN FAIRLY DRY ALOFT AND SO THE NORTHERN PORTION OF THE FRONT CARRIES ONLY LOW TOPPED ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE FRONT N OF 25N. LOWER LEVEL MOISTURE BECOMES MORE PLENTIFUL S OF 25N W OF 91W AS THE FRONT FALLS BENEATH MORE FAVORABLE MIDDLE TO UPPER LEVEL DYNAMICS DUE TO AN UPPER LEVEL RIDGE WITH AXIS EXTENDING ALONG THE SPINE OF CENTRAL AMERICA FROM WESTERN PANAMA NW TO 20N90W. THE MORE ACTIVE CONVECTION ALONG THE FRONT HAS DISSIPATED OVER THE PAST 6 HOURS LEAVING ONLY SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THE FRONT S OF 25N BETWEEN 93W-96W. AN EARLIER RECENT ASCAT PASS AROUND 04/0244 UTC SHOWED STRONG N-NW WINDS IN WAKE OF THE FRONT ACROSS THE NORTH-CENTRAL AND WESTERN GULF WATERS. THE FRONT WILL SWEEP EAST OF THE GULF BY LATE FRIDAY AS HIGH PRESSURE ACCOMPANIED BY NORTHERLY WINDS SETTLES IN ACROSS THE BASIN FOR THE WEEKEND. CARIBBEAN SEA... WATER VAPOR SHOWS AN UPPER LEVEL TROUGH AXIS EXTENDS FROM THE SW NORTH ATLC INTO THE WESTERN CARIBBEAN ALONG 25N69W TO A BASE NEAR 12N77W. DRY AIR AND STRONG SUBSIDENCE ALOFT IS NOTED W OF THE TROUGH AXIS UNDER NW FLOW. THESE STABLE CONDITIONS ALOFT ALONG WITH NORTHEASTERLY SURFACE WINDS ARE MAINTAINING FAIR CONDITIONS THIS MORNING W OF 73W. HOWEVER WEAK SURFACE CONVERGENCE IS NOTED OVER A PORTION OF THE NW CARIBBEAN WITH ISOLATED SHOWERS OCCURRING FROM 17N-20N BETWEEN 84W-88W. THE REMAINDER OF THE EASTERN CARIBBEAN FALLS EAST OF THE UPPER LEVEL TROUGH AXIS AND THEREFORE TROPICAL MOISTURE STREAMS NORTHEASTWARD FROM NORTHERN SOUTH AMERICA ACROSS THE MONA PASSAGE REGION...PUERTO RICO...AND THE LESSER ANTILLES THIS MORNING. SCATTERED TO NUMEROUS SHOWERS AND SCATTERED TSTMS ARE OCCURRING OVER THE NE CARIBBEAN N OF 15N BETWEEN 63W-70W IN RESPONSE TO MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE. A FEW ISOLATED SHOWERS AND TSTMS ARE ALSO OCCURRING CLOSER TO THE BASE OF THE UPPER LEVEL TROUGH AND IN AN AREA OF MAXIMUM LOW-LEVEL MOISTURE CONVERGENCE FROM 11N-14N BETWEEN 70W-73W...AND S OF 11N BETWEEN 75W-82W. ATLANTIC OCEAN... A MAJORITY OF THE W ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE EXTENDING INTO THE DISCUSSION AREA FROM A GRADUALLY WEAKENING 1016 MB HIGH CENTERED OFF THE NORTH CAROLINA COAST NEAR 34N69W. THE RIDGE AXIS CARRIES SW FROM THE HIGH TO THE BAHAMAS NEAR 25N77W WITH MOSTLY FAIR CONDITIONS THIS EVENING W OF 65W. WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL TROUGH AXIS EXTENDS FROM 32N63W TO 20N73W IN SUPPORT OF A DISSIPATING COLD FRONT ANALYZED FROM 32N53W TO 27N64W. ISOLATED SHOWERS ARE OCCURRING N OF 26N BETWEEN 50W AND THE FRONT WHILE FARTHER SW SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 300 NM EAST OF A SURFACE TROUGH EXTENDING FROM NEAR 27N60W TO 19N68W. THE REMAINDER OF THE EASTERN ATLC IS CONTROLLED BY A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH CENTERED NEAR 31N34W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING ON THE SOUTHWESTERN PERIPHERY OF THE RIDGE FROM 11N-18N BETWEEN 40W-48W. OTHERWISE...A DISSIPATING STATIONARY FRONT EXTENDS INTO THE EASTERN PERIPHERY OF THE RIDGE SOUTH OF THE CANARY ISLANDS ALONG 28N10W TO 27N17W WITH STRONG NW WINDS REMAINING N OF 28N E OF 18W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN