000 AXNT20 KNHC 240001 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE OCT 23 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM SANDY IS CENTERED NEAR 14.8N 77.5W AT 24/0000 UTC OR ABOUT 196 NM SSW OF KINGSTON JAMAICA MOVING NNE AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 993 MB. MAXIMUM SUSTAINED MAXIMUM WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 10N-19W BETWEEN 72W-79W...AND FROM 15N-21N BETWEEN 67W-72W. WIDELY SCATTERED MODERATE CONVECTION IS SW OF THE CENTER FROM 10N-14N BETWEEN 79W-82W. HURRICANE WARNINGS ARE IN EFFECT FOR JAMAICA AND MANY CUBAN PROVINCES. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. TROPICAL DEPRESSION NINETEEN IS CENTERED NEAR 26.3N 50.0W AT 23/2100 UTC OR ABOUT 860 NM NE OF THE LEEWARD ISLANDS MOVING NNE AT 12 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED MAXIMUM WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 25N-31N BETWEEN 45W-51W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 17N31W TO 12N30 TO 8N28W W MOVING W AT 10-15 KT. A 1008 MB LOW IS CENTERED AT THE SOUTHERN EXTENT OF THE WAVE AXIS AT 8N28W. BROAD LOW-LEVEL CYCLONIC FLOW IS NOTED IN GLOBAL MODEL STREAMLINE ANALYSIS BETWEEN 25W-35W. SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. TROPICAL WAVE EXTENDS FROM 16N40W TO 9N38W MOVING W AT 5-10 KT. BROAD LOW-LEVEL CYCLONIC TURNING OF THE LOW-LEVEL CLOUD FIELD IS NOTED BETWEEN 35W-45W. SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N15W TO 8N20W TO 8N30W TO 10N37W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 8N40W TO 7N44W TO 9N50W TO 9N55W. ISOLATED MODERATE CONVECTION IS FROM 4N-14N BETWEEN 20W-25W. ...DISCUSSION... GULF OF MEXICO... A 1021 MB HIGH IS CENTERED OVER N GEORGIA NEAR 34N84W. A SURFACE RIDGE AXIS EXTENDS SW TO THE BAY OF CAMPECHE. FAIR WEATHER DOMINATES THE GULF OF MEXICO. 10-15 KT E-SE WINDS ARE NOTED. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE GULF WITH AXIS ALONG 82W. STRONG SUBSIDENCE COVERS THE ENTIRE GULF. EXPECT CONVECTION ASSOCIATED WITH T.S. SANDY TO ADVECT OVER S FLORIDA AND THE STRAITS OF FLORIDA IN 24 HOURS. CARIBBEAN SEA... T.S. SANDY IS OVER THE CENTRAL CARIBBEAN PRODUCING A CONSIDERABLE AMOUNT OF CONVECTION. SEE ABOVE. BROAD CYCLONIC SURFACE WINDS COVER THE ENTIRE CARIBBEAN AND CENTRAL AMERICA. HEAVY RAINFALL OVER JAMAICA...EASTERN CUBA...AND HISPANIOLA MAY RESULT IN LIFE- THREATENING FLASH FLOODS AND MUD SLIDES... ESPECIALLY IN AREAS OF HIGHER TERRAIN. STORM SURGE WILL ALSO REMAIN A KEY IMPACT FOR THE SOUTHERN AND EASTERN COASTS OF JAMAICA AS THE SURGE WILL BE ACCOMPANIED BY LARGE AND DESTRUCTIVE WAVES. ELSEWHERE... ISOLATED MODERATE CONVECTION IS INLAND OVER HONDURAS...NICARAGUA...AND COSTA RICA. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE NW CARIBBEAN WITH STRONG SUBSIDENCE. UPPER LEVEL RIDGING IS OVER THE CENTRAL AND EASTERN CARIBBEAN WITH CONSIDERABLE UPPER LEVEL CLOUDS AND MOISTURE. EXPECT T.S. SANDY TO INTENSIFY AND MOVE NORTHERLY OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A 1022 MB HIGH IS CENTERED ALONG THE COAST OF NORTH CAROLINA NEAR 34N77W. SURFACE HIGH PRESSURE RIDGING IS OVER THE W ATLANTIC WITH FAIR WEATHER. A DISSIPATING COLD FRONT VOID OF CONVECTION IS OVER THE CENTRAL ATLANTIC FROM 32N52W TO 26N60W TO 24N70W. T.D. NINETEEN IS OVER THE CENTRAL ATLANTIC. SEE ABOVE. TWO 1016 MB HIGHS ARE OVER THE E ATLANTIC AT 29N38W AND 23N27W. A SURFACE TROUGH IS IN BETWEEN THE HIGHS FROM 24N34W TO 20N40W. SCATTERED SHOWERS ARE WITHIN 120 NM OF THE TROUGH AXIS. EXPECT T.D. NINETEEN TO INTENSIFY AND MOVE NE OVER THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA