000 AXNT20 KNHC 131801 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT OCT 13 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM RAFAEL IS CENTERED NEAR 16.5N 63.9W AT 13/1800 UTC OR ABOUT 87 NM SE OF ST. CROIX MOVING N AT 8 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. 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. AN UPPER RIDGE TO THE E OF THE LESSER ANTILLES IS ENHANCING THE DEEP CONVECTION AND DRAWING THE CONVECTION E OF THE LESSER ANTILLES. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 13N-17N BETWEEN 60W-64W INCLUDING PORTIONS OF THE WINDWARD AND LEEWARD ISLANDS. SCATTERED MODERATE/STRONG CONVECTION COVERS THE AREA FROM 9N-13N BETWEEN 59W-60W AND WITHIN 90 NM OF LINE FROM 15N57W 19N61W TO 19N64W INCLUDING PORTIONS OF THE LEEWARD AND VIRGIN ISLANDS. TROPICAL DEPRESSION PATTY WAS DOWNGRADED AT 13/1500 UTC TO POST-TROPICAL CYCLONE. THE REMNANTS OF PATTY IS CENTERED NEAR 24.8N 72.6W AT 13/1500 UTC OR ABOUT 191 NM E-NE OF THE CENTRAL BAHAMAS MOVING W-SW AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1010 MB. MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. THIS IS THE LAST ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER. THE AREA IS VOID OF ANY DEEP CONVECTION WITH POSSIBLE ISOLATED SHOWERS WITHIN 60/75 NM OF LINE FROM 26N70W TO 24N74W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM THE CAPE VERDE ISLANDS NEAR 17N30W TO 12N33W MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY AND AT THE BASE OF AN UPPER TROUGH. SCATTERED MODERATE/ STRONG CONVECTION FROM 11N-15N BETWEEN 29W-34W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF LINE FROM 15N30W TO 19N26W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL ATLC NEAR 13N16W TO 12N20W WHERE THE ITCZ AXIS BEGINS S OF THE TROPICAL WAVE NEAR 11N32W CONTINUING ALONG 10N36W TO 10N56W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120 NM OF LINE FROM 14N25W ACROSS THE ITCZ TO 4N33W... WITHIN 120 NM N OF THE ITCZ BETWEEN 34W-54W...AND WITHIN 180 NM S OF THE ITCZ BETWEEN 38W-50W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE COVERS THE GULF THIS AFTERNOON W OF 86W EXTENDING FROM ACROSS MEXICO INTO THE GULF NEAR TAMPICO TO OVER THE N GULF COAST NEAR ALABAMA/MISSISSIPPI. AN UPPER TROUGH COVERS THE REMAINDER OF THE GULF E OF 86W WITH THE TROUGH AXIS IN THE W ATLC. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 30 NM ALONG THE COAST OF MEXICO BETWEEN VERACRUZ LAGUNA MORALES. THE SURFACE RIDGE HAS BUILT OVER THE GULF ANCHORED OVER PENNSYLVANIA WITH DRY STABLE UPPER AIR DOMINATING MOST OF THE GULF. THUS...THE REMAINDER OF THE GULF IS UNDER MOSTLY CLEAR SKIES THIS AFTERNOON. HIGH PRESSURE WILL SHIFT E ON MON AND TUE. A COLD FRONT WILL APPROACH THE TEXAS COAST BY LATE WED. CARIBBEAN SEA... THE PRIMARY CONCERN THIS AFTERNOON IS TROPICAL STORM RAFAEL IN THE E CARIBBEAN...SEE SPECIAL FEATURES ABOVE. THE NARROW UPPER TROUGH OVER THE E GULF OF MEXICO EXTENDS S OVER THE NW CARIBBEAN ACROSS CENTRAL CUBA TO E HONDURAS GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 15N-18N BETWEEN 79W-86W TO INLAND OVER HONDURAS. SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS ARE FROM OVER JAMAICA TO INLAND ACROSS CUBA BETWEEN 74W-78W. AN UPPER RIDGE EXTENDS ACROSS THE S CARIBBEAN FROM THE W TROPICAL ATLC ACROSS THE WINDWARD ISLANDS TO S NICARAGUA COVERING THE REMAINDER OF THE BASIN. THIS UPPER RIDGE IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 75/90 NM ALONG THE COAST OF NICARAGUA. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 9N75W ALONG 10N80W THEN ACROSS COSTA RICA INTO THE E PACIFIC REGION NEAR 10N83W GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N BETWEEN 75W-82W. THIS IS LEAVING THE CENTRAL CARIBBEAN WITH FAIR WEATHER THIS AFTERNOON. T.S. RAFAEL IS EXPECTED TO MOVE NNW ACROSS THE CARIBBEAN TODAY THEN ACROSS THE VIRGIN ISLANDS THIS EVENING AND TONIGHT WHILE SLOWLY INTENSIFYING. STRONG NE WINDS WILL CONTINUE ACROSS THE NW CARIBBEAN THROUGH TONIGHT AS STRONG HIGH PRESSURE BUILDS OVER E CONUS. WINDS AND SEAS WILL DIMINISH ACROSS THE ENTIRE CARIBBEAN SUN THROUGH WED. ATLANTIC OCEAN... THE REMNANTS OF PATTY REMAINS NE OF THE CENTRAL BAHAMA ISLANDS THIS AFTERNOON...SEE SPECIAL FEATURES ABOVE. THE UPPER TROUGH OVER THE E GULF OF MEXICO AND THE NW CARIBBEAN EXTENDS OVER THE W ATLC N OF 27N W OF 70W THEN NARROWS AS IT CROSSES CUBA INTO THE NW CARIBBEAN WITH STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT. THE UPPER TROUGH IS SUPPORTING A COLD FRONT N OF THE DISCUSSION AREA WITH A STATIONARY FRONT EXTENDING FROM 32N63W TO 28N69W AND GENERATING SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120/150 NM E OF FRONT. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE ALSO FROM OVER THE BAHAMA ISLANDS TO CUBA BETWEEN 72W-79W. AN UPPER LOW IS IN THE E ATLC CENTERED NEAR 21N36W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-24N BETWEEN 34W-38W AND ENHANCING THE ACTIVITY ASSOCIATED WITH THE TROPICAL WAVE. THE REMAINDER OF THE ATLC BASIN N OF THE TROPICS IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1027 MB HIGH JUST N OF THE DISCUSSION AREA NEAR 35N37W. AN UPPER RIDGE IN THE W TROPICAL ATLC EXTENDS FROM 13N59W N ALONG 23N57W TO 30N56W PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 18N-26N BETWEEN 54W-67W AND WITHIN 120/150 NM OF LINE FROM 12N52W TO 18N57W. T.S. RAFAEL IS EXPECTED TO MOVE ACROSS THE VIRGIN ISLANDS THIS EVENING AND TONIGHT WHILE SLOWLY INTENSIFYING... REACHING NEAR 19.2N 65.2W EARLY SUN...THEN CONTINUE NNW AND GRADUALLY INTENSIFY TO 60 KT...REACHING 22.6N 67.0W EARLY MON...THEN MOVE NORTHWARD AND EXIT THE REGION MON AND TUE. REMNANTS OF PATTY WILL DISSIPATE THIS EVENING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW