000 AXNT20 KNHC 140552 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN OCT 14 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. ...SPECIAL FEATURES... TROPICAL STORM RAFAEL IS CENTERED NEAR 18.7N 63.6W AT 14/0600 UTC OR ABOUT 45 NM NW OF SAINT MARTIN OR ABOUT 90 NM NE OF SAINT CROIX MOVING N AT 12 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. WIDELY SCATTERED STRONG AND SCATTERED MODERATE CONVECTION IS FROM 13N-24N BETWEEN 60W-65W. WIDELY SCATTERED MODERATE CONVECTION IS ELSEWHERE FROM 11N-26N BETWEEN 54W-66W. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N34W TO 17N35W MOVING W AT 10-15 KT. BROAD AND WEAK CYCLONIC FLOW IS NOTED IN THE VICINITY OF THE WAVE AXIS AS IT COINCIDES WITH MAXIMUM MOISTURE VALUES IN RECENT TOTAL PRECIPITABLE WATER IMAGERY FROM 07N-14N BETWEEN 33W-37W. SCATTERED MODERATE CONVECTION IS FROM 10N-14N BETWEEN 33W-36W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W TO 09N24W TO 09N33W TO 07N37W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N37W TO 06N42W TO 08N48W. SCATTERED MODERATE CONVECTION IS FROM 04N-16N BETWEEN 20W-35W...AND FROM 07N-10N BETWEEN 47W-50W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL RIDGE IS CENTERED OVER THE WESTERN GULF PROVIDING NW TO N FLOW ALOFT WITH WATER VAPOR IMAGERY INDICATING DRY AIR AND SUBSIDENCE DOMINATES. AT THE SURFACE...A RIDGE INFLUENCES THE ENTIRE GULF BASIN ANCHORED BY A 1031 MB HIGH CENTERED OFF THE MID-ATLC COAST NEAR 39N71W. THE RIDGE AXIS EXTENDS SW ALONG THE EAST COAST OF THE U.S. TO THE SW GULF WITH CLEAR SKIES NOTED ON SATELLITE IMAGERY THIS EVENING. THE SURFACE RIDGE IS FORECAST TO REMAIN ACROSS THE BASIN THROUGH TUESDAY. CARIBBEAN SEA... AN UPPER LEVEL TROUGH AXIS EXTENDS SOUTHWESTWARD FROM OVER THE SW NORTH ATLC TO OVER THE NW CARIBBEAN ALONG 22N81W TO 12N87W. NW OF THE TROUGH AXIS...WATER VAPOR IMAGERY INDICATES VERY DRY NORTHERLY FLOW WHICH IS PROVIDING FOR OVERALL STABLE CONDITIONS ACROSS THE NW CARIBBEAN THIS EVENING. EAST OF THE UPPER LEVEL TROUGH AXIS...A CORRIDOR OF MIDDLE TO UPPER LEVEL MOISTURE IS NOTED ON WATER VAPOR IMAGERY EXTENDING FROM 11N84W TO 21N77W. MID-LEVEL LIFTING DYNAMICS AND LOW-LEVEL MOISTURE CONVERGENCE IS GENERATING ISOLATED SHOWERS AND TSTMS ACROSS CUBA...THE ADJACENT COASTAL WATERS BETWEEN CUBA...THE CAYMAN ISLANDS...AND JAMAICA...AND AN AREA FROM 12N-18N BETWEEN 79W-84W. ACROSS THE SW CARIBBEAN...THE MONSOON TROUGH AXIS EXTENDS EASTWARD FROM THE EASTERN PACIFIC REGION ALONG 10N/11N AND IS PROVIDING FOCUS FOR ISOLATED SHOWERS AND TSTMS ACROSS NORTHERN AND WESTERN COLOMBIA...AND WESTERN PANAMA. FINALLY...TROPICAL STORM RAFAEL IS CENTERED OVER THE NE CARIBBEAN AND LIES ON THE WESTERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 16N59W. THE UPPER LEVEL HIGH IS PROVIDING AMPLE DIFFLUENCE FOR THE NUMEROUS SHOWERS AND SCATTERED STRONG TSTMS OCCURRING WITH RAFAEL AT THIS TIME. RAFAEL IS FORECAST TO TRACK ON AN OVERALL NORTHERLY TRACK OVER THE NEXT SEVERAL DAYS. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH AXIS EXTENDS INTO THE DISCUSSION AREA NEAR 32N72W SW TO 22N81W AND INTO THE NW CARIBBEAN SEA. VERY DRY AIR ALOFT IS ASSOCIATED WITH THIS TROUGH WHICH IS RESULTING IN MOSTLY FAIR CONDITIONS FOR PORTIONS OF THE SW NORTH ATLC N OF 27N AND W OF 78W. A FEW ISOLATED LOW-TOPPED SHOWERS ARE HOWEVER OCCURRING OVER THIS AREA USHERED IN BY BRISK NORTHEASTERLY WINDS. TO THE EAST OF THE UPPER LEVEL TROUGH AXIS OVER THE REMAINDER OF THE SW NORTH ATLC...A SURFACE TROUGH IS ANALYZED FROM 21N75W TO 27N72W AND IS PROVIDING LOW-LEVEL FOCUS FOR ISOLATED SHOWERS FROM 20N-27N BETWEEN 72W-79W. SE OF THE SURFACE TROUGH...CONVECTION FROM TROPICAL STORM RAFAEL CONTINUES TO IMPACT PORTIONS OF THE ATLC WATERS FROM 11N-32N BETWEEN 54W-67W. RAFAEL IS FORECAST TO MOVE ON A NORTHERLY TRACK THROUGH LATE MONDAY AND BEGIN A GRADUAL N TO NE TRACK AS THE UPPER LEVEL TROUGHING MOVES EASTWARD. ELSEWHERE THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A BROAD SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED NEAR 35N34W. EMBEDDED WITHIN THE SURFACE RIDGE...AN UPPER LEVEL LOW IS NOTED ON WATER VAPOR IMAGERY CENTERED NEAR 22N35W AND IS GENERATING ISOLATED SHOWERS AND TSTMS FROM 19N-24N BETWEEN 33W-39W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN