000 AXNT20 KNHC 071807 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE MAY 07 2013 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. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GAMBIA NEAR 12N16W TO 7N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 7N20W TO 2N30W WHERE IT STRADDLES THE EQUATOR TO ALONG 42W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 180 NM N OF THE ITCZ BETWEEN 28W AND 37W. WIDELY SCATTERED MODERATE CONVECTION IS ALONG THE ITCZ TO THE EQUATOR BETWEEN 20W AND 40W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS ALSO NOTED WELL S OF THE MONSOON TROUGH FROM 2N-4N BETWEEN 8W-12W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC... A 1020 MB HIGH IS OVER THE NW GULF OF MEXICO NEAR 26N92W. LIGHT AND VARIABLE SURFACE WINDS OF 5 TO 10 KT ARE NOTED OVER MOST OF THE GULF ASSOCIATED WITH THE HIGH. THESE WINDS RESULTED IN SEAS OF ONLY 1-2 FT OVER THE GULF. BROKEN TO OVERCAST LOW CLOUDS REMAIN OVER THE FAR SW GULF AND BAY OF CAMPECHE WITHIN A 180 NM RADIUS OF VERACRUZ MEXICO. A CONCENTRATED LINE OF LOW AND MID LEVEL CLOUDS EXTENDING FROM THE FLORIDA COAST NEAR CEDAR KEY TO 28.5N86.5W MARKED THE TRAILING END OF A SURFACE TROUGH WHICH EXTENDED FROM A DEEP LAYERED CYCLONE OVER NE GEORGIA. NATIONAL COMPOSITE RADAR IMAGERY SHOWS WEAKENING SCATTERED SHOWERS WITHIN 15 NM OF THE TROUGH. ELSEWHERE CLEAR SKIES WITH A FEW PATCHES OF CUMULIFORM CLOUDS WERE NOTED. IN THE UPPER LEVELS...A LARGE DEEP LAYERED CYCLONE IS CENTERED OVER EXTREME NE GEORGIA AND NW SOUTH CAROLINA WITH MODERATE TO STRONG UPPER LEVEL WESTERLY WINDS AND SUBSIDENCE OVER FLORIDA. HIGH PRESSURE IS FORECAST TO MOVE EASTWARD OVER THE NEXT 48 HOURS WITH RETURN SE FLOW SPREADING E OVER THE GULF. CARIBBEAN SEA... A SURFACE TROUGH EXTENDS FROM S OF HISPANIOLA NEAR 17N71W TO NW VENEZUELA NEAR 12N72W. WIDELY SCATTERED SHOWERS ARE WITHIN 120 NM OF THE TROUGH N OF 15N. A MORE CONCENTRATED AREA OF SHOWERS AND THUNDERSTORMS WAS OVER THE NE CARIBBEAN N OF 16N E OF 70W SPREADING NW OVER PUERTO RICO AND TOWARD THE DOMINICAN REPUBLIC. ADDITIONALLY...SCATTERED SHOWERS AND ISOLATED MODERATE CONVECTION WAS OVER VENEZUELA AND COLOMBIA FROM 2N-7N BETWEEN 66W-76W. TRADE WINDS OVER THE CARIBBEAN WERE LIGHTER THAN NORMAL WITH MOST OF THE AREA EXPERIENCING WINDS AROUND 10 KT...A FEW AREAS IN THE CARIBBEAN E OF THE TROUGH AXIS REPORTED E TO SE WINDS OF 15 KT. TRADEWINDS TURNED MORE NORTHERLY W OF THE TROUGH AXIS...BUT REMAINED LIGHT. IN THE UPPER LEVELS...THE WESTERN PORTION OF AN UPPER LEVEL HIGH IS PRODUCING SW UPPER LEVEL FLOW OVER THE CARIBBEAN SEA WITH STRONG SUBSIDENCE OVER THE W CARIBBEAN W OF 72W AND SIGNIFICANT UPPER LEVEL MOISTURE AND BROKEN HIGH CLOUD OVER THE E CARIBBEAN. THE SURFACE TROUGH IS FORECAST TO WEAKEN OVER THE NEXT 48 HOURS AS IT TRACKS TO THE W. A MORE NORMAL TRADE WIND REGIME IS FORECAST TO DEVELOP WITH 15 TO 20 KT WINDS EXPANDING ACROSS THE CENTRAL CARIBBEAN BETWEEN 70W AND 78W. ATLANTIC OCEAN... AS OF 1500 UTC...A COLD FRONT EXTENDED INTO THE AREA THROUGH 32N75W TO ANDROS ISLAND IN THE BAHAMAS. TO THE EAST...A WARM FRONT EXTENDED FROM 32N71W TO NE OF THE BAHAMAS NEAR 26N65W. SCATTERED SHOWERS AND THUNDERSTORMS WERE WITHIN 180 NM NE OF THE WARM FRONT. FURTHER E...A STATIONARY 1012 MB LOW IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N39W. A SURFACE TROUGH EXTENDS FROM THE LOW THROUGH 31N36W TO 26N40W. THE LEADING COLD FRONT EXTENDED FROM 32N25W TO 26N30W TO 22N37W...WHERE IT BECAME A DISSIPATING FRONT/SHEAR LINE THROUGH 20N45W TO JUST NE OF THE LEEWARD ISLANDS NEAR 19N62W. WIDELY SCATTERED SHOWERS ARE WITHIN 180 NM SE OF THE COLD FRONT N OF 28N...AND WITHIN 90 NM OF THE FRONT ELSEWHERE E OF 40W. IN THE UPPER LEVELS...MOSTLY ZONAL FLOW IS N OF 20N BETWEEN 50W-80W. FURTHER E...A BROAD TROUGH N OF 25N EXTENDED BETWEEN 30W AND 50W WITH AN EMBEDDED DEEP LAYERED CYCLONE NEAR 32N38W. AN UPPER LEVEL TROUGH IS OVER THE E ATLANTIC E OF 30W. THE OCCLUDED FRONTAL SYSTEMS OVER THE NW ATLC ARE FORECAST TO MOVE SLOWLY E...WHILE THE CENTRAL ATLANTIC COLD FRONT MOVES STEADILY E WITH SHOWERS AND CONVECTION WANING AS UPPER LEVEL SUPPORT WEAKENS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE AT THE REQUEST OF METEO-FRANCE AND THE METEOROLOGICAL SERVICES OF HAITI AND THE DOMINICAN REPUBLIC...THE TROPICAL ANALYSIS AND FORECAST BRANCH (TAFB) WILL BEGIN PROVIDING...ON A TEMPORARY BASIS...A SEPARATE DETAILED SECTION WITHIN THE ATLANTIC TROPICAL WEATHER DISCUSSION (TWDAT). IT WILL COVER BOTH HAITI AND THE DOMINICAN REPUBLIC DUE TO THE SHARED GEOGRAPHY OF BOTH COUNTRIES ON THE ISLAND OF HISPANIOLA. THE SECTION BEGINS ON MAY 15 2013 AT 1800 UTC...2 PM EDT. IT WILL PROVIDE GUIDANCE FOR SIGNIFICANT WEATHER EVENTS THAT ARE EXPECTED TO IMPACT THE REGION THROUGH 48 HOURS...WITH THE FOCUS ON ASSESSING THE POTENTIAL FOR HEAVY RAINFALL. $$ COBB