000 AXNT20 KNHC 130549 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURE... A 1009 MB GALE CENTER IS IN THE E ATLC CENTERED NEAR 34N31W. A BROAD UPPER LEVEL LOW COVERS THE AREA N OF 24N BETWEEN 20W-43W SUPPORTING THE GALE CENTER AND A MID LEVEL CENTER NEAR 33N36W. CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 120 NM OF LINE FROM 36N27W TO 32N36W. 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 8N12W TO 5N17W WHERE THE ITCZ CONTINUES ALONG 4N21W 6N36W TO 3N46W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 4N TO THE EQUATOR E OF 4W ACROSS THE PRIME MERIDIAN. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60 NM OF LINE FROM 7N28W TO 8N39W. ...DISCUSSION... GULF OF MEXICO... A LOW AMPLITUDE UPPER TROUGH EXTENDS FROM TEXAS ACROSS THE LOWER MISSISSIPPI VALLEY INCLUDING THE NW GULF N OF 28N W OF 90W WITH A SHORTWAVE UPPER TROUGH EXTENDING FROM N MISSISSIPPI TO SE LOUISIANA ALL SUPPORTING AT 13/0300 UTC A 1016 MB LOW OVER CENTRAL MISSISSIPPI AND A COLD FRONT EXTENDING FROM THE LOW INTO THE GULF OVER NEW ORLEANS ALONG 28N91W TO 27N92W WHERE IT BECOMES STATIONARY ALONG 25N95W TO INLAND OVER MEXICO NEAR LAGUNA MADRE. A SURFACE TROUGH AS INDICATED BY A WIND SHIFT FOLLOWS THE FRONT EXTENDING FROM JUST W OF VERMILION BAY LOUISIANA TO 27N95W. SCATTERED TO HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE WITHIN 250 NM E OF THE COLD FRONT WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF THE STATIONARY FRONT W OF 95W. A HIGH AMPLITUDE UPPER RIDGE COVERS THE REMAINDER OF THE GULF WITH THE AXIS EXTENDING FROM AN UPPER HIGH INLAND OVER HONDURAS THROUGH THE YUCATAN CHANNEL TO ACROSS THE FLORIDA PENINSULA CONTINUING ALONG THE E CONUS COAST TO NEW ENGLAND. A SURFACE TROUGH IS BENEATH THE UPPER RIDGE EXTENDING FROM 23N90W ACROSS THE BAY OF CAMPECHE TO S MEXICO NEAR 17N94W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 90 NM EITHER SIDE OF THE TROUGH AXIS. THE UPPER TROUGH WILL GRADUALLY SHIFT EASTWARD OVERNIGHT. THE WEAK FRONT WILL MOVE EASTWARD 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/ISOLATED THUNDERSTORMS OVER THE CENTRAL CARIBBEAN N OF 14N TO INLAND OVER HISPANIOLA BETWEEN 69W-74W. FRESH TO STRONG EASTERLY TRADE WINDS ARE BANKING LOW LEVEL CLOUDS WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND AND WITHIN 60 NM ALONG THE COAST OF PANAMA. THE REMAINDER OF THE CARIBBEAN IS UNDER MOSTLY CLEAR SKIES TONIGHT. SURFACE RIDGE OVER THE W ATLC WILL STRENGTHEN THE PRESSURE GRADIENT CONTINUING THE TRADE WINDS THROUGH MID WEEK. ATLANTIC OCEAN... A HIGH AMPLITUDE UPPER RIDGE THAT COVERS PORTIONS OF THE GULF OF MEXICO AND CARIBBEAN EXTENDS A RIDGE AXIS ACROSS THE FLORIDA PENINSULA CONTINUING ALONG THE E CONUS COAST TO NEW ENGLAND COVERING THE W ATLC W OF 70W. A SURFACE RIDGE COVERS THE W ATLC W OF THE FRONT DESCRIBED BELOW AND ANCHORED BY A 1028 MB HIGH ABOUT 175 NM E OF THE NORTH CAROLINA COAST. A HIGH AMPLITUDE UPPER TROUGH IS OVER THE REMAINDER OF THE W ATLC BETWEEN 50W-70W EXTENDING S OVER THE E CARIBBEAN AND SUPPORTING A COLD FRONT AT 13/0300 UTC THAT ENTERS THE W ATLC NEAR 32N59W TO 27N65W WHERE A SHEAR AXIS CONTINUES TO E OF THE BAHAMA ISLANDS NEAR 25N73W. A SURFACE TROUGH EXTENDS FROM 26N63W TO NEAR 22N64W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90 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 W ATLC COLD FRONT WILL SINK SLOWLY SE AND DISSIPATE THROUGH SUN. SURFACE RIDGE OVER THE W ATLC WILL CONTINUE THROUGH LATE SUN. A WEAK COLD FRONT WILL MOVE ACROSS THE SE CONUS MON WITH A WEAK FRONTAL BOUNDARY MOVING OFF OF THE NE FLORIDA COAST BY LATE WED. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW