000 AXNT20 KNHC 102352 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN OCT 10 2010 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... A 1007 MB LOW IS CENTERED IN THE SW CARIBBEAN SEA NEAR 13N81W. A SURFACE TROUGH IS ANALYZED N-NW FROM THE LOW ALONG 16N81W TO 20N79W. ELONGATED CYCLONIC TURNING OF THE LOW-LEVEL CLOUD FIELD IS NOTED ON SATELLITE IMAGERY WITH STRONGEST LOW-LEVEL CONVERGENCE LOCATED NW OF THE LOW CENTER BETWEEN THE SURFACE TROUGH AXIS AND NICARAGUA COAST. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS OCCURRING FROM 13N-17N BETWEEN 80W-84W. SIMILAR CONVECTION IS ALSO OCCURRING WELL NORTH OF THE LOW FROM 17N-21N BETWEEN 74W-81W...INCLUDING JAMAICA AND PORTIONS OF EASTERN CUBA. AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER EASTERN HONDURAS NEAR 15N84W COVERING MUCH OF THE WESTERN CARIBBEAN SEA. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE UPPER LEVEL ANTICYCLONE IS LIKELY ENHANCING THE ONGOING CONVECTION. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N70W TO 19N66W MOVING W AT 15 KT. THE WAVE IS BECOMING EMBEDDED WITHIN LARGER SYNOPTIC-SCALE TROUGHING THAT EXTENDS FROM THE CENTRAL ATLC TO THE GREATER ANTILLES AND COVERS MUCH OF THE CARIBBEAN SEA BASIN. WHILE THE WAVE CONTINUES MOVING WESTWARD WITHIN AN AREA FAVORABLE FOR LIFT...CLOUDINESS...AND PRECIPITATION...INCREASED VALUES OF TOTAL PRECIPITABLE WATER ARE NOTED IMAGERY FROM 10N-18N BETWEEN 62W-68W. WHILE NO SIGNIFICANT DEEP CONVECTION IS OBSERVED ON SATELLITE IMAGERY THIS EVENING...ISOLATED SHOWERS ARE OCCURRING WITHIN 240 NM E OF THE WAVE AXIS...WITH SAN JUAN PUERTO RICO DOPPLER RADAR RECEIVING SOME OF THESE PRECIPITATION RETURNS THIS EVENING. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N15W 07N20W 08N33W 05N50W 06N60W. SCATTERED MODERATE CONVECTION IS FROM 02N-07N BETWEEN 18W-22W. SIMILAR CONVECTION IS WITHIN 120 NM OF A LINE FROM 10N35W TO 07N48W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY SHOWS A VERY DRY AND STABLE AIRMASS ALOFT OVER THE GULF THIS EVENING. THIS UPPER LEVEL FEATURE SUPPORTS A 1019 MB SURFACE HIGH CENTERED NEAR 27N90W. THE LARGE AND EXPANSIVE SURFACE HIGH IS PROVIDING FOR LIGHT WINDS ACROSS THE ENTIRE BASIN. STRONG SUBSIDENCE IS FORECAST TO CONTINUE OVER THE GULF THE NEXT FEW DAYS AS THE SURFACE HIGH DRIFTS EASTWARD. AS THIS OCCURS...10-15 KT SOUTHERLY WINDS ARE EXPECTED OVER THE FAR WESTERN GULF WATERS EARLY MONDAY INTO TUESDAY. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER PUERTO RICO NEAR 18N67W AND EXTENDS AN UPPER LEVEL RIDGE AXIS NE OVER THE CENTRAL ATLC TO 28N44W AND W-SW TO ANOTHER UPPER LEVEL ANTICYCLONE CENTERED OVER EASTERN HONDURAS NEAR 15N84W. OVER THE WESTERN CARIBBEAN...THE SPECIAL FEATURE 1007 MB LOW LOCATES NEAR 13N81W WITH A SURFACE TROUGH EXTENDING TO EASTERN CUBA. SCATTERED SHOWERS AND TSTMS ARE LOCATED WITHIN 180 NM OF A LINE FROM 13N84W TO 22N75W. FARTHER EAST...A TROPICAL WAVE IS MOVING ACROSS THE EASTERN CARIBBEAN ANALYZED FROM NW VENEZUELA NEAR 10N70W TO 19N66W. ISOLATED SHOWERS ARE WITHIN 240 NM E OF THE WAVE AXIS...IMPACTING THE US/UK VIRGIN ISLANDS AS WELL AS THE ABC ISLANDS. ATLANTIC OCEAN... MUCH OF THE W ATLC IS UNDER THE INFLUENCE OF DRY SOUTHWESTERLY FLOW ALOFT ON THE NORTHERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONE CENTERED OVER PUERTO RICO NEAR 18N67W. THIS UPPER LEVEL FLOW N OF 20N IS SUPPORTING SURFACE RIDGING OVER THE W ATLC W OF 65W AND GENERALLY FAIR CONDITIONS THIS EVENING. AS THE REMNANTS OF OTTO AS A 988 MB LOW NEAR 39N38W RACE NORTHEASTWARD OVER THE CENTRAL ATLC NORTH OF THE DISCUSSION AREA...A FORMING COLD FRONT EXTENDS FROM THE LOW TO 32N41W WITH SURFACE TROUGHING CONTINUING SW FROM THERE TO 25N56W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 150 NM E OF THE BOUNDARY. FARTHER TO THE W-SW A SURFACE TROUGH IS ANALYZED FROM 24N60W TO THE WINDWARD PASSAGE NEAR 20N73W. LOW-LEVEL CONVERGENCE IN THE VICINITY OF THE SURFACE TROUGH AXIS IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS OVER A LARGE PORTION OF THE W ATLC FROM 20N-26N BETWEEN 56W-77W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 27N31W THAT IS PROVIDING FAIR CONDITIONS N OF 13N E OF 40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN