000 AXNT20 KNHC 062349 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAY 06 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N13W TO 05N19W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N19W TO 01N32W TO THE EQUATOR NEAR 41W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 03N-07N BETWEEN 15W-29W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL CUT-OFF LOW IS CENTERED OVER THE SE CONUS AND SUPPORTS A COLD FRONT THAT CROSS THE SOUTHERN FLORIDA PENINSULA AND EMERGES INTO THE SE GULF NEAR 26N82W AND EXTENDS WESTWARD TO 25N93W. A FEW ISOLATED SHOWERS ARE NOTED ON MOSAIC DOPPLER RADAR WITHIN 30 NM EITHER SIDE OF THE FRONT E OF 83W...HOWEVER THE REMAINDER OF THE FRONT REMAINS A MOSTLY DRY FEATURE THIS EVENING. ELSEWHERE...THE GULF IS UNDER THE INFLUENCE OF SURFACE RIDGING ANCHORED BY A 1020 MB HIGH CENTERED NEAR 28N95W. THE RIDGE WILL BUILD SOUTHEAST OVER THE NEXT 24 TO 36 HOURS AS THE COLD FRONT MOVES EAST OF THE REGION BY TUESDAY. CARIBBEAN SEA... SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW IS OVER MUCH OF THE CARIBBEAN THIS EVENING WITH WATER VAPOR IMAGERY INDICATING A WIDE SWATH OF MOISTURE MOVING NORTHWARD OFF THE SOUTH AMERICA CONTINENT...OVER THE EASTERN CARIBBEAN AND INTO PORTIONS OF THE CENTRAL ATLC. WHILE MIDDLE TO UPPER LEVEL MOISTURE AND INSTABILITY ARE MAXIMIZED OVER THE CENTRAL AND EASTERN CARIBBEAN...A SURFACE TROUGH IS ANALYZED FROM THE SOUTHERN COAST OF PUERTO RICO NEAR 18N67W TO THE COAST OF NW VENEZUELA NEAR 11N68W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 210 NM EITHER SIDE OF THE SURFACE TROUGH AXIS AND ACROSS PORTIONS OF THE NE CARIBBEAN N OF 16N E OF 67W. THE REMAINDER OF THE WESTERN CARIBBEAN IS UNDER THE INFLUENCE OF FAIRLY DRY AIR ALOFT AND N-NE WINDS IN THE RANGE OF 5 TO 15 KT THIS EVENING. CONDITIONS REMAIN FAIR WITH CLEAR SKIES DOMINATING. THE SURFACE TROUGH WILL CONTINUE TO SLOWLY DRIFT WESTWARD OVER THE NEXT FEW DAYS WHILE BECOMING DIFFUSE AS E-NE TRADE WIND FLOW RE- ESTABLISHES ITSELF AS THE DOMINATING WEATHER PATTERN BY THURSDAY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL CUT-OFF LOW IS CENTERED OVER THE SE CONUS THIS EVENING THAT SUPPORTS A SERIES OF FRONTS LOCATED IN THE SW NORTH ATLC WATERS. THE WESTERN-MOST COLD FRONT IS ANALYZED FROM THE SOUTH CAROLINA COAST NEAR 34N79W AND ARCS S-SW TO 30N78W TO THE FLORIDA PENINSULA COAST NEAR 27N80W. THIS FRONT REMAINS BENEATH DRY AIR ALOFT AND THEREFORE VERY LITTLE PRECIPITATION IS NOTED ON DOPPLER RADAR OR SATELLITE IMAGERY IN THE VICINITY OF THE FRONT AT THIS TIME. HOWEVER...A FEW POSSIBLE ISOLATED SHOWERS ARE MOVING ACROSS THE SOUTHERN FLORIDA PENINSULA AND ARE EXPECTED TO BE SHORT-LIVED. THE SECONDARY FRONTAL SYSTEM IS A COMBINATION OF AN OCCLUDED FRONT STRETCHING FROM THE NORTH CAROLINA COAST NEAR 34N78W TO A TRIPLE POINT NEAR 31N75W. FROM THERE A DISSIPATING COLD FRONT IS ANALYZED TO 27N74W TO THE CENTRAL BAHAMAS NEAR 24N77W. NO PRECIPITATION IS ASSOCIATED WITH THIS COLD FRONT AS THE DRY AIR ALOFT REMAINS IN PLACE. THE CONVECTIVE ACTIVITY IS MOSTLY ASSOCIATED WITH A STATIONARY FRONT THAT EXTENDS FROM THE TRIPLE POINT NEAR 31N75W TO 26N70W TO 24N60W. ISOLATES SHOWERS AND TSTMS ARE OCCURRING WITHIN 240 NM NORTHEAST OF THE BOUNDARY IN AN AREA OF MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE. FARTHER EAST...ANOTHER MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 34N43W WITH A TROUGH AXIS EXTENDING WELL NE OF THE LOW TO BEYOND 44N25W. THIS TROUGHING SUPPORTS A STATIONARY FRONT ANALYZED FROM 32N28W SW TO 25N40W TO 21N55W WHERE IT BEGINS TO DISSIPATE TO NORTH OF PUERTO RICO NEAR 19N67W. WHILE MIDDLE TO UPPER LEVEL MOISTURE CONTINUES TO STREAM NORTHEASTWARD...THE FRONT IS PROVIDING FOR SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING WITHIN 210 NM SOUTH OF THE FRONT AND ISOLATED SHOWERS OCCURRING WITHIN 150 NM NORTH OF THE FRONT. AS FOR THE UPPER LEVEL LOW...IT REFLECTS TO THE SURFACE AS A 1010 MB LOW CENTERED NEAR 34N45W WITH A SURFACE TROUGH EXTENDING INTO THE DISCUSSION AREA NEAR 32N41W TO 28N44W TO 27N52W. POSSIBLE ISOLATED SHOWERS ARE OCCURRING WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH AXIS. FINALLY...A SURFACE RIDGE IS MAINTAINING CONTROL OVER THE EASTERN ATLC ANCHORED BY A 1024 MB HIGH CENTERED NEAR 37N10W. THE RIDGE AXIS EXTENDS FROM THE HIGH TO 30N19W TO 22N30W TO A 1016 MB HIGH CENTERED NEAR 17N46W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE AT THE REQUEST OF METEO-FRANCE AND THE METEROLOGICAL 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. $$ HUFFMAN