000 AXNT20 KNHC 151158 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON OCT 15 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURES... TROPICAL STORM RAFAEL IS CENTERED NEAR 22.5N 65.5W AT 15/1200 UTC OR ABOUT 250 NM N OF SAN JUAN PUERTO RICO AND ABOUT 590 NM S OF BERMUDA MOVING N-NW AT 8 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 985 MB. MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 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. NUMEROUS STRONG CONVECTION IS FROM 21N-24N BETWEEN 65W-67W. SCATTERED/NUMEROUS STRONG CONVECTION IS WITHIN 45 NM OF LINE FROM 18N62W 20N62W TO 22N61W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF LINE FROM 16N59W TO 21N61W AND COVERS THE REMAINDER OF THE AREA FROM 21N-27N BETWEEN 59W-67W. ...TROPICAL WAVES... A TROPICAL WAVE WAS ADDED AT 15/0600 UTC EXTENDING ALONG 31W FROM 8N-14N MOVING W NEAR 10 KT. WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/ STRONG CONVECTION WITHIN 60/75 NM EITHER SIDE OF THE WAVE AXIS. TROPICAL WAVE EXTENDS FROM 20N40W TO 10N41W MOVING W NEAR 10 KT. WAVE IS AT THE LEADING EDGE OF A MODERATE SURGE OF MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY AND AT THE BASE OF AN UPPER TROUGH. ANY CONVECTION IN THE VICINITY IS ASSOCIATED WITH THE UPPER TROUGH. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W ALONG 9N19W TO 7N25W WHERE THE ITCZ AXIS CONTINUES ALONG 6N32W 8N41W 7N49W 8N54W TO SOUTH AMERICA NEAR 7N59W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 4N-11N BETWEEN 32W-38W AND WITHIN 90 NM OF LINE FROM 8N50W 10N54W TO 15N58W. CLUSTERS OF SCATTERED MODERATE CONVECTION IS WITHIN 120 NM ALONG THE COAST OF LIBERIA/SIERRA LEONE AND WITHIN 90 NM S OF THE MONSOON TROUGH/ITCZ BETWEEN 24W-28W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER TROUGH IS INLAND OVER THE E CONUS SUPPORTING A WEAK COLD FRONT AT 15/0900 UTC IS ALONG THE COAST OF TEXAS WITH A PRE-FRONTAL SURFACE TROUGH EXTENDING THE LOUISIANA COAST NEAR 29N93W TO INLAND OVER S TEXAS S OF CORPUS CHRISTI. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS IMMEDIATELY ALONG THE SURFACE TROUGH. A BROAD UPPER RIDGE COVERS THE GULF WATERS W OF 86W EXTENDING FROM ACROSS MEXICO INTO THE GULF BETWEEN TAMPICO AND TUXPAN TO NEAR 26N86W. A NARROW UPPER TROUGH COVERS THE REMAINDER OF THE GULF E OF 86W WITH THE TROUGH AXIS EXTENDING FROM THE W ATLC THROUGH THE STRAITS OF FLORIDA TO OVER CUBA NEAR 23N80W INTO THE NW CARIBBEAN. ISOLATED SHOWERS/THUNDERSTORMS ARE S OF 24N BETWEEN 81W-87W INCLUDING THE YUCATAN CHANNEL. A WEAK SURFACE RIDGE IS BRIDGING THE FRONT COVERING THE W GULF AND ANCHORED OVER OKLAHOMA. THE REMAINDER OF THE GULF IS UNDER MOSTLY CLEAR SKIES THIS MORNING. THE COLD FRONT WILL MOVE SE ACROSS THE N GULF LATER TODAY AND REACH FROM NEAR FORT MYERS TO CORPUS CHRISTI BY TUE EVENING WHERE IT WILL STALL AND GRADUALLY DISSIPATE. A STRONGER FRONT WILL MOVE OFF THE TEXAS COAST EARLY THU AND REACH FROM CEDAR KEY FLORIDA TO N OF TAMPICO MEXICO FRI MORNING. CARIBBEAN SEA... THE NARROW UPPER TROUGH OVER THE E GULF OF MEXICO EXTENDS INTO THE NW CARIBBEAN ACROSS CUBA NEAR 23N80W INTO THE GULF OF HONDURAS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM OF LINE FROM THE S COAST OF CUBA NEAR 21N80W TO THE COAST OF HONDURAS NEAR 15N84W. ISOLATED SHOWERS/THUNDERSTORMS ARE N OF 20N BETWEEN 85W-87W INCLUDING THE YUCATAN CHANNEL. AN UPPER RIDGE COVERS THE REMAINDER OF THE CARIBBEAN ANCHORED NEAR 15N68W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE NE CARIBBEAN N OF 14N E OF 65W TO OVER THE LEEWARD AND VIRGIN ISLANDS WITH ISOLATED CLUSTERS OF SIMILAR ACTIVITY DOTTING THE E CARIBBEAN E OF 70W...ALL ASSOCIATED WITH OUTER BANDS OF TROPICAL STORM RAFAEL. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 11N74W ALONG 12N78W THEN ACROSS S NICARAGUA/ COSTA RICA INTO THE E PACIFIC REGION NEAR 11N84W GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 12N BETWEEN 75W-83W AND FROM 12N-14N BETWEEN 80W AND THE COAST OF NICARAGUA. THIS IS LEAVING THE CENTRAL CARIBBEAN WITH MOSTLY FAIR WEATHER THIS MORNING. RAFAEL WILL INTENSIFY TO HURRICANE TODAY AS IT CONTINUES TO MOVE N-NW AWAY FROM THE CARIBBEAN. WINDS AND SEAS WILL DIMINISH ACROSS THE ENTIRE CARIBBEAN THROUGH FRI WITH SWELLS FROM RAFAEL MOVING THROUGH NE CARIBBEAN PASSAGES TODAY THROUGH TUE AND DIMINISHING ON WED. ATLANTIC OCEAN... THE PRIMARY CONCERN THIS MORNING REMAINS TROPICAL STORM RAFAEL N OF PUERTO RICO...SEE SPECIAL FEATURES ABOVE. THE NARROW UPPER TROUGH OVER THE E GULF OF MEXICO AND THE NW CARIBBEAN EXTENDS OVER THE W ATLC THROUGH 32N72W ALONG 25N77W THROUGH THE STRAITS OF FLORIDA AND ACROSS CUBA NEAR 23N80W. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT ARE W OF THE UPPER TROUGH AXIS. A SURFACE TROUGH EXTENDS FROM 29N75W TO 24N74W WITH SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM 26N74W TO BEYOND 32N68W. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC BETWEEN 50W-70W PROVIDING DIFFLUENCE ALOFT TO ENHANCE THE ACTIVITY ABOVE AND THE ACTIVITY ASSOCIATED WITH TROPICAL STORM RAFAEL. A BROAD UPPER TROUGH EXTENDS FROM THE E ATLC AND THE CANARY ISLANDS ALONG 29N27W TO AN UPPER LOW NEAR 21N39W TO THE BASE NEAR 12N48W IN THE W TROPICAL ATLC GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 10N-15N BETWEEN 33W-42W INCLUDING THE VICINITY OF THE TROPICAL WAVE AND THE CAPE VERDE ISLANDS. A SURFACE TROUGH LIES ALONG THE WESTERN EDGE OF THE UPPER TROUGH EXTENDING FROM 29N44W TO 20N48W. THE CENTRAL AND E ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1023 MB HIGH JUST N OF THE DISCUSSION AREA NEAR 34N36W. RAFAEL WILL MOVE N-NW AND INTENSIFY TO HURRICANE STRENGTH BY AFTERNOON THEN BE ABOUT 350 NM S OF BERMUDA LATE TONIGHT THEN BEGIN TO TURN NNE AND GRADUALLY ACCELERATE TUE AND BE ABOUT 200 NM E-NE OF BERMUDA TUE NIGHT/WED MORNING. A COLD FRONT WILL PUSH THROUGH THE NW HALF TUE THROUGH WED DISSIPATING THU. ANOTHER COLD FRONT MOVES INTO NW WATERS FRI. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW