000 AXNT20 KNHC 222348 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON OCT 22 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 2245 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION EIGHTEEN IS NOW TROPICAL STORM SANDY. AS OF 23/0000 UTC...SANDY IS CENTERED NEAR 12.7N 78.7W...OR ABOUT 335 NM SSW OF KINGSTON JAMAICA. THE STORM IS MOMENTARILY STATIONARY WITH A 24 HOUR POSITION JUST SLIGHTLY TO THE NORTH. MINIMUM CENTRAL PRESSURE IS 998 MB. MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KT WITH GUSTS TO 50 KT. A TROPICAL STORM WATCH HAS BEEN PLACED FOR JAMAICA AND HAITI. 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. SCATTERED MODERATE/STRONG CONVECTION IS ACROSS THE SW CARIBBEAN FROM 10N-13N BETWEEN 76W-83W...FROM 13N-16N BETWEEN 72W-79W. ACTIVITY ALSO SPREADS FARTHER NORTH AND EAST ACROSS HISPANIOLA AND EASTERN CUBA. TROPICAL DEPRESSION NINETEEN HAS FORMED AS OF 22/2100 UTC. T.D. 19 IS CENTERED NEAR 22.3N 51.7W...OR ABOUT 650 NM ENE OF THE LEEWARD ISLANDS. THE SYSTEM IS MOVING N AT 6 KT. MINIMUM CENTRAL PRESSURE IS 1006. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SEE LATEST NHC PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC AND THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE/STRONG CONVECTION IS FROM 21N-25N BETWEEN 47W-52W. ISOLATED MODERATE CONVECTION IS FROM 20N-23N BETWEEN 51W-53W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 17N24W TO 10N25W MOVING W AT 10-15 KT. THE WAVE LIES JUST WEST OF AN AREA OF MAXIMUM MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. ONLY ISOLATED MODERATE CONVECTION IS FROM 8N-12N BETWEEN 21W-24W...AND FROM 12N-14N BETWEEN 28W-30W. TROPICAL WAVE IS ALONG 16N37W TO 10N37W MOVING W AT 5-10 KT. THE WAVE COINCIDES WITH A NARROW SURGE IN DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. A CLUSTER OF SCATTERED STRONG CONVECTION IS JUST EAST OF THE WAVE EMBEDDED WITHIN THE MONSOON TROUGH FROM 8N-11N BETWEEN 33W-36W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS WEST AFRICA TO THE COAST OF SIERRA LEONE AT 9N13W CONTINUING ALONG 9N20W 10N31W 10N43W. THE ITCZ BEGINS AT 10N43W AND CONTINUES ALONG 10N50W 8N54W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 3N-7N BETWEEN 17W-19W...AND FROM 7N-9N BETWEEN 42W-47W. ...DISCUSSION... GULF OF MEXICO... SURFACE RIDGING CONTINUES TO DOMINATE THE GULF OF MEXICO TONIGHT ANCHORED BY A 1023 MB HIGH OVER NORTH CAROLINA. ANTI-CYCLONIC FLOW OF 10-15 KT IS AROUND THE RIDGE EXCEPT FOR SOME STRONGER WINDS UP TO 15 KT ACROSS THE SE GULF AND ALONG THE SOUTHERN TEXAS COAST. CLEAR SKIES ARE PRESENT OVER THE MAJORITY OF THE AREA WITH A FEW LOW-LEVEL CLOUDS AND POSSIBLE SHOWERS ACROSS THE FAR SE GULF AND THE FAR SW GULF ALONG THE MEXICAN COAST. ALOFT...AN UPPER LEVEL RIDGE COVERS THE EASTERN CONUS INTO THE GULF OF MEXICO SUPPORTING THE SURFACE RIDGE. AN UPPER LEVEL TROUGH STILL EXTENDS DOWN THE FLORIDA PENINSULA INTO THE NW CARIBBEAN. DRY AIR AND SUBSIDENCE ALSO COVER THE BASIN HELPING SUPPORT THE FAIR WEATHER. SURFACE RIDGING IS EXPECTED TO REMAIN ACROSS THE GULF FOR THE NEXT SEVERAL DAYS PROVIDING GENERALLY FAIR CONDITIONS. CARIBBEAN SEA... WHAT IS NOW TROPICAL STORM SANDY DOMINATES THE WEATHER PATTERN IN THE CARIBBEAN PROVIDING ABUNDANT MOISTURE TO A GOOD PORTION OF THE AREA. SEE SPECIAL FEATURES FOR MORE DETAILS. SHOWERS/THUNDERSTORMS COVER MUCH OF THE SW CARIBBEAN AND INTO THE CENTRAL AND EASTERN CARIBBEAN. SIMILAR ACTIVITY ALSO COVERS MUCH OF CENTRAL AMERICA LIKELY ASSOCIATED WITH THE MONSOON TROUGH THAT EXTENDS ACROSS SOUTHERN NICARAGUA TOWARD SANDY. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER HISPANIOLA AND WILL LIKELY SPREAD INTO EASTERN CUBA AND JAMAICA SOON. AS THE SYSTEM GRADUALLY MOVES NORTHWARD OVER THE NEXT FEW DAYS...HEAVY ACTIVITY IS LIKELY OVER THESE ISLANDS AND POSE THE RISK FOR FLOODING AND MUDSLIDES ESPECIALLY IN HIGH TERRAIN. ALOFT...AN UPPER LEVEL TROUGH EXTENDS FROM THE FLORIDA PENINSULA TO NORTH OF HONDURAS. DRY AIR IS SINKING SOUTH AROUND THE WEST SIDE OF THE TROUGH PROVIDING FAIR CONDITIONS OVER THE FAR NW CARIBBEAN. AN UPPER LEVEL RIDGE COVERS THE REMAINDER OF THE BASIN WITH AXIS ALONG 70W. DRY AIR IS ALSO WRAPPING AROUND THE FAR EASTERN SIDE OF THE UPPER RIDGE PROVIDING FAIR WEATHER OVER THE FAR EASTERN CARIBBEAN INCLUDING THE LESSER ANTILLES. T.S. SANDY WILL CONTINUE TO DOMINATE THE CARIBBEAN FOR THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... AN UPPER LEVEL RIDGE OVER THE EASTERN CONUS IS HELPING SUPPORT SURFACE RIDGING AND FAIR WEATHER DOWN THE EASTERN SEABOARD WHICH CONTINUES INTO THE WEST ATLC. AN UPPER LEVEL TROUGH ALONG 60W SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N59W TO 27N63W WHERE IT TRANSITIONS INTO A DISSIPATING STATIONARY FRONT TO 26N69W AND THEN INTO A SHEAR AXIS TO THE CENTRAL BAHAMAS NEAR 24N77W. SCATTERED SHOWERS/THUNDERSTORMS COVER MUCH OF THE BAHAMAS TO CUBA. POSSIBLE SHOWERS ARE ALONG THE FRONTAL BOUNDARY ELSEWHERE. IN THE CENTRAL ATLC...NEWLY FORMED T.D. NINETEEN IS SUPPORTING AN AREA OF SHOWERS/THUNDERSTORMS TO THE NE OF THE CENTER. AN UPPER LEVEL TROUGH IS WEST OF THE SYSTEM WITH AXIS ALONG 54W. AN UPPER LEVEL RIDGE TO THE EAST ALONG 44W AND CONTINUING TO NEAR 12N30W IN THE TROPICAL ATLC SUPPORTS WEAK SURFACE RIDGING TO THE NE OF T.D. NINETEEN. HOWEVER...A LARGE LOW PRESSURE SYSTEM DOMINATES THE NE ATLC SUPPORTED BY AN UPPER LEVEL LOW NEAR THE AZORES ISLANDS. NO ACTIVE WEATHER IS ASSOCIATED WITH THE SYSTEM IN THE DISCUSSION AREA. A WEAK SURFACE TROUGH IS ANALYZED ALONG 23N34W TO 19N36W...BUT IS NOT SUPPORTING ANY SHOWERS ACTIVITY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON