000 AXNT20 KNHC 301145 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI NOV 30 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 1115 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 9N13W TO 7N15W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 5N18W 6N27W 4N39W 7N48W TO SOUTH AMERICA NEAR 5N54W. A 1009 MB LOW IS JUST N OF THE ITCZ CENTERED NEAR 9N46W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 9N-10N BETWEEN 45W AND THE LOW. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 75/90 NM FROM 4N19W 5N13W TO THE COAST OF W AFRICA NEAR 6N10W AND WITHIN 90 NM OF LINE FROM 6N27W TO 9N21W. SCATTERED MODERATE CONVECTION IS FROM 6N-7N BETWEEN 30W-33W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE S OF 11N TO INLAND OVER SOUTH AMERICA BETWEEN 55W-60W. THIS AREA PREVIOUSLY HOSTED A SURFACE TROUGH. ...DISCUSSION... GULF OF MEXICO... A SHORTWAVE UPPER TROUGH EXTENDS OVER THE MISSISSIPPI VALLEY TO OVER THE NW GULF NEAR 24N93W. THE BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN EXTENDS OVER THE REMAINDER OF THE GULF. A WEAK SURFACE TROUGH IS ALONG THE COAST OF MEXICO FROM 23N97W TO 20N95W. A SURFACE RIDGE COVERS MOST OF THE GULF AND W ATLC ANCHORED BY A 1031 MB HIGH OFF THE COAST OF NORTH CAROLINA. THE SOUTHERLY RETURN FLOW AROUND THE RIDGE AND THE SURFACE TROUGH ALONG THE COAST OF MEXICO ARE GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS N OF 21N W OF 93W TO INLAND OVER TEXAS AND MEXICO. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE SE GULF FROM 23N-27N BETWEEN 80W-90W INCLUDING S FLORIDA...THE STRAITS OF FLORIDA...AND THE FLORIDA KEYS. THIS IS LEAVING THE REMAINDER OF THE GULF WITH FAIR WEATHER THIS MORNING. A BROAD SURFACE RIDGE WILL GRADUALLY SHIFT E THROUGH TUE. CARIBBEAN SEA... BROAD UPPER RIDGE DOMINATES THE CARIBBEAN ANCHORED NE VENEZUELA NEAR 9N62W AND EXTENDING A RIDGE AXIS N ACROSS THE LEEWARD ISLANDS TO OVER THE W/CENTRAL ATLC. A SURFACE TROUGH IS IN THE W ATLC TO OVER HAITI GENERATING ISOLATED SHOWERS IN THE N PORTION OF THE WINDWARD PASSAGE. A SECOND SURFACE TROUGH EXTENDS OVER THE LEEWARD ISLANDS GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM MONTSERRAT NORTHWARD E OF 63W TO ACROSS THE ISLANDS. THE MODERATE TO FRESH EASTERLY TRADE WINDS AND COUPLED WITH THE MONSOON TROUGH THAT EXTENDS ALONG 9N BETWEEN COLOMBIA TO COSTA RICA ARE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 10N TO INLAND OVER COSTA RICA AND PANAMA. REMNANT LOW CLOUDS WITH ISOLATED SHOWERS REMAIN OVER THE FAR NW CARIBBEAN S OF 21N W OF 83W LEAVING THE REMAINDER OF THE CARIBBEAN WITH FAIR WEATHER THIS MORNING. A SURFACE RIDGE OVER THE W ATLC WILL MAINTAIN TRADE WINDS THROUGH TUE. ATLANTIC OCEAN... THE BROAD UPPER RIDGE ANCHORED OVER THE CARIBBEAN EXTENDS AN AXIS ACROSS THE LEEWARD ISLANDS TO 30N60W COVERING THE AREA W OF 50W. AN UPPER TROUGH N OF 30N BETWEEN 47W-65W CONTINUES TO SUPPORT A DISSIPATING COLD FRONT THAT ENTERS THE W/CENTRAL ATLC THROUGH 32N53W EXTENDING TO 27N60W WHERE IT BECOMES SHEAR LINE ALONG 24N69W TO 21N71W. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 32N49W TO 27N54W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 75 NM E OF THE TROUGH. A SURFACE RIDGE CONTINUES TO BUILD W OF THE FRONT COVERING THE W ATLC AND THE GULF OF MEXICO ANCHORED BY A 1031 MB HIGH JUST OFF THE NORTH CAROLINA COAST. TO THE SOUTH...A SURFACE TROUGH EXTENDS FROM THE TURKS AND CAICOS NEAR 22N73W TO OVER HAITI NEAR 19N72W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-23N BETWEEN 70W-74W. A SECOND SURFACE TROUGH EXTENDS FROM 21N62W TO OVER THE LEEWARD ISLANDS TO MONTSERRAT GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 16N-21N BETWEEN 60W-63W. AN UPPER TROUGH IS IN THE E/CENTRAL ATLC FROM 28N45W ALONG 20N40W TO 11N40W SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 24N51W THROUGH A WEAK 1012 MB LOW NEAR 20N49W TO 18N48W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ASSOCIATED WITH THE UPPER TROUGH ARE WITHIN 120/150 NM OF LINE FROM 21N39W TO 30N43W. A BROAD SURFACE RIDGE DOMINATES THE ATLC E OF 43W AND ANCHORED BY A 1034 MB HIGH N OF THE AZORES. THE SHEAR LINE WILL MEANDER OVER W/CENTRAL ATLC THROUGH SAT AND GRADUALLY MOVE INTO THE CENTRAL ATLC BY TUE. REINFORCING HIGH PRESSURE MOVING INTO THE W ATLC SUN THROUGH TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW