000 AXNT20 KNHC 052350 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAY 05 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 11N15W TO 02N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 02N20W TO THE EQUATOR NEAR 24W THEN ALONG THE EQUATOR TO 40W TO 02N43W. A SURFACE TROUGH ANALYZED FROM 02N46W TO 04N43W REMAINS EMBEDDED WITHIN THE WESTERN EXTENT OF THE ITCZ. WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 06N BETWEEN 13W- 24W...AND FROM THE EQUATOR TO 05N BETWEEN 35W-49W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL CUT-OFF LOW IS CENTERED OVER NORTHERN ALABAMA AND SUPPORTS A COLD FRONT THAT ENTERS THE NE GULF NEAR 30N86W AND EXTENDS SW TO 28N90W THEN TO THE TEXAS COAST NEAR 27N97W. ISOLATED SHOWERS ARE OCCURRING WITHIN 30 NM EITHER SIDE OF THE FRONT E OF 90W. OTHERWISE...THE REMAINDER OF THE GULF IS UNDER MOSTLY CLEAR SKIES AND FAIR CONDITIONS AS DRY NORTHWESTERLY FLOW ALOFT CONTINUES TO PROVIDE A SUBSIDENT ENVIRONMENT FOR THE BASIN THIS EVENING. HOWEVER...LOW-LEVEL CLOUDS AND MOISTURE INCREASE OVER THE SW GULF S OF 22N W OF 90W. THE COLD FRONT WILL MOVE EAST OF THE GULF BY LATE MONDAY WITH SURFACE RIDGING REMAINING IN CONTROL FOR THE UPCOMING WEEK. CARIBBEAN SEA... SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW IS OVER MUCH OF THE CARIBBEAN THIS EVENING AS THE OVERALL SURFACE PRESSURE PATTERN REMAINS RELATIVELY WEAK AND SLIGHTLY MODIFIED FROM THE USUAL E- NE TRADE WIND FLOW. AN AREA OF SURFACE TROUGHING IS ESTABLISHED OVER THE SW NORTH ATLC S OF 27N WHICH STRETCHES SOUTHWARD AND COVERS THE BASIN BETWEEN 62W-76W. WEAK SOUTHERLY WINDS ARE NOTED E OF 67W AS ISOLATED SHOWERS REMAIN POSSIBLE THROUGH THE OVERNIGHT HOURS ACROSS PORTIONS OF THE LESSER ANTILLES AND ADJACENT COASTAL WATERS. A SURFACE TROUGH EXTENDS ACROSS HISPANIOLA FROM 18N74W NORTHEASTWARD INTO THE ATLC PROVIDING FOCUS FOR ISOLATED SHOWERS WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...W OF 74W...N-NW WINDS IN THE RANGE OF 5 TO 15 KT CONTINUE TO FILTER IN ACROSS THE WESTERN CARIBBEAN AND ARE FORECAST TO PERSIST THROUGH LATE MONDAY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL CUT-OFF LOW IS CENTERED OVER NORTHERN ALABAMA THIS EVENING THAT SUPPORTS A COLD FRONT ANALYZED FROM THE SOUTH CAROLINA COAST NEAR 32N81W TO 29N79W WHICH THEN BECOMES STATIONARY TO A 1010 MB LOW CENTERED NEAR 25N72W. WITH UPPER LEVEL DIFFLUENCE MAXIMIZED TO THE E-SE OF THE UPPER LEVEL LOW AND A SURFACE FRONT IN PLACE...SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 210 NM NORTHEAST OF THE FRONT. FARTHER EAST...WATER VAPOR IMAGERY INDICATES A MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 37N48W WITH A TROUGH AXIS EXTENDING WESTWARD ALONG 33N TO THE CAROLINA COAST. THIS TROUGHING SUPPORTS A 1007 MB LOW CENTERED NEAR 33N33W AND THE ASSOCIATED COLD FRONT ANALYZED FROM THE LOW CENTER TO 30N36W TO 25N45W TO 23N54W WHERE IT BECOMES STATIONARY TO 25N63W AND INTO THE AFOREMENTIONED 1010 MB LOW NEAR 25N72W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 300 NM SOUTHEAST OF THE COLD FRONT AND WITHIN 240 NM EITHER SIDE OF THE STATIONARY FRONT ACROSS MUCH OF THE CENTRAL AND SW NORTH ATLC. IN ADDITION...A SURFACE TROUGH EXTENDS FROM THE STATIONARY FRONT NEAR 23N62W TO HISPANIOLA NEAR 19N70W. ISOLATED SHOWERS ARE OCCURRING WITHIN 150 NM EITHER SIDE OF THE SURFACE TROUGH. FINALLY...A SURFACE RIDGE IS MAINTAINING CONTROL OVER THE EASTERN ATLC ANCHORED BY A 1022 MB HIGH CENTERED NEAR 36N14W. THE RIDGE AXIS EXTENDS FROM THE HIGH TO 30N20W TO 22N33W. 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