000 AXNT20 KNHC 131039 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN MAY 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURE... A 1010 MB GALE CENTER IS IN THE E ATLC CENTERED NEAR 35N32W. A BROAD UPPER LEVEL LOW COVERS THE AREA N OF 24N BETWEEN 20W-45W SUPPORTING THE GALE CENTER AND A MID LEVEL CENTER NEAR 32N36W. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 150 NM OF LINE FROM 38N28W TO 30N35W. THERE IS SOME POTENTIAL FOR ADDITIONAL DEVELOPMENT AS THE SYSTEM MOVES LITTLE DURING THE NEXT COUPLE OF DAYS AND THE LOW HAS A MEDIUM CHANCE OF BECOMING A SUBTROPICAL OR TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ADDITIONAL SPECIAL TROPICAL WEATHER OUTLOOKS WILL BE ISSUED ON THIS SYSTEM SUNDAY...IF NECESSARY. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N14W TO 6N18W WHERE THE ITCZ CONTINUES ALONG 4N23W 5N43W TO INLAND OVER SOUTH AMERICA NEAR 3N51W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM THE COAST OF SW AFRICA TO JUST S OF THE EQUATOR E OF 4W ACROSS THE PRIME MERIDIAN. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 60 NM OF 8N BETWEEN 34W-42W. ...DISCUSSION... GULF OF MEXICO... A BROAD LOW AMPLITUDE UPPER TROUGH EXTENDS FROM TEXAS ACROSS THE LOWER MISSISSIPPI VALLEY INCLUDING THE NW GULF N OF 28N W OF 88W WITH A SHORTWAVE UPPER TROUGH EXTENDING FROM NE MISSISSIPPI TO MOBILE ALABAMA ALL SUPPORTING AT 13/0900 UTC A 1015 MB LOW OVER NE MISSISSIPPI AND A WEAK COLD FRONT EXTENDING FROM THE LOW INTO THE GULF NEAR GULFPORT MISSISSIPPI ALONG 28N89W TO 26N92W WHERE IT BECOMES STATIONARY TO INLAND OVER MEXICO NEAR LAGUNA MADRE. A SURFACE TROUGH AS INDICATED BY A WIND SHIFT FOLLOWS THE FRONT EXTENDING FROM JUST W OF NEW ORLEANS LOUISIANA TO 28N96W. SCATTERED TO HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE N OF 25N TO INLAND OVER THE N GULF COAST W OF 84W TO THE COLD FRONT. A SURFACE TROUGH IS OVER THE SW GULF EXTENDING FROM 23N91W ACROSS THE BAY OF CAMPECHE TO S MEXICO NEAR 18N94W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90 NM EITHER SIDE OF THE TROUGH AXIS. A HIGH AMPLITUDE UPPER RIDGE COVERS THE REMAINDER OF THE GULF WITH THE AXIS EXTENDING FROM AN UPPER HIGH INLAND OVER HONDURAS ACROSS W CUBA AND THE S FLORIDA PENINSULA CONTINUING ALONG THE E CONUS COAST TO THE CANADIAN MARITIMES. THE UPPER FLOW CONVERGING WITH THE EASTERLY SURFACE FLOW ARE GENERATING SCATTERED TO HEAVY SHOWERS AND SCATTERED THUNDERSTORMS S OF THE STATIONARY FRONT W OF 94W. THE WEAK FRONT WILL MOVE E ACROSS THE N GULF THROUGH LATE MON. CARIBBEAN SEA... AN UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE CARIBBEAN TO 75W AND IS ANCHORED BY AN UPPER HIGH INLAND OVER HONDURAS. THE UPPER TROUGH OVER THE W ATLC EXTENDS S OVER THE E CARIBBEAN E OF 75W. THE UPPER TROUGH IS GENERATING CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER THE CENTRAL CARIBBEAN N OF 15N TO INLAND OVER HISPANIOLA BETWEEN 70W-77W INCLUDING W JAMAICA. FRESH TO STRONG EASTERLY TRADE WINDS CONTINUE TO BANK LOW LEVEL CLOUDS WITH SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS S OF 10N TO INLAND OVER PANAMA. THE REMAINDER OF THE CARIBBEAN IS UNDER MOSTLY CLEAR SKIES THIS MORNING. SURFACE RIDGE OVER THE W ATLC WILL MAINTAIN THE TRADE WINDS THROUGH MID WEEK. THE WINDS WILL START TO DIMINISH THU AS THE W ATLC RIDGE WEAKENS. ATLANTIC OCEAN... A HIGH AMPLITUDE UPPER RIDGE THAT COVERS PORTIONS OF THE GULF OF MEXICO AND CARIBBEAN EXTENDS A RIDGE AXIS ACROSS THE S FLORIDA PENINSULA CONTINUING ALONG THE E CONUS COAST TO THE CANADIAN MARITIMES COVERING THE W ATLC W OF 70W. A SURFACE RIDGE COVERS THE W ATLC W OF THE FRONT DESCRIBED BELOW AND ANCHORED BY A 1027 MB HIGH JUST OFF THE NORTH CAROLINA COAST. A HIGH AMPLITUDE UPPER TROUGH IS OVER THE REMAINDER OF THE W ATLC BETWEEN 53W-70W EXTENDING S OVER THE E CARIBBEAN AND SUPPORTING A WEAK COLD FRONT AT 13/0900 UTC THAT ENTERS THE W ATLC NEAR 32N58W TO 28N62W WHERE IT BECOMES STATIONARY TO 26N66W AND A SHEAR AXIS CONTINUES TO E OF THE BAHAMA ISLANDS NEAR 24N73W. A SURFACE TROUGH IS SE OF THE FRONT EXTENDING FROM 27N62W TO 21N62W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120 NM OF 59W BETWEEN 20N-25N. A NARROWING SURFACE RIDGE COVERS THE CENTRAL ATLC N OF 15N BETWEEN 40W AND THE ABOVE FRONT. THE UPPER LOW OVER THE E ATLC IS DESCRIBED IN THE SPECIAL FEATURES ABOVE. THE WEAK FRONT/SHEAR LINE WILL SINK SLOWLY SE AND DISSIPATE THROUGH THIS AFTERNOON. THE W ATLC SURFACE RIDGE WILL MIGRATE E FROM THE CAROLINAS TO THE N CENTRAL ATLC MAINTAINING MODERATE TO FRESH NE TO E WINDS MAINLY N OF 25N THROUGH LATE SUN. A WEAK COLD FRONT WILL MOVE OFF OF THE NE FLORIDA COAST BY THU. 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