000 AXNT20 KNHC 081806 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE OCT 08 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. ...SPECIAL FEATURES... A 1012 MB LOW PRESSURE CENTER IS EMBEDDED WITHIN THE MONSOON TROUGH AXIS ABOUT 350 NM SW OF THE SOUTHERNMOST CAPE VERDE ISLANDS. THIS LOW IS WITHIN AN AREA OF MIDDLE-LEVEL DIFFLUENCE...WHICH IS SUPPORTING SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS FROM 07N-12N BETWEEN 26W-29W. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR GRADUAL DEVELOPMENT OF THIS DISTURBANCE DURING THE NEXT COUPLE OF DAYS. THERE IS A MEDIUM CHANCE FOR IT TO BECOME A TROPICAL CYCLONE DURING THE NEXT 48 HOURS WHILE IT CONTINUES TO MOVE SLOWLY WEST-NORTHWESTWARD. ...TROPICAL WAVES... A TROPICAL WAVE IS ACROSS THE CAPE VERDE ISLANDS WITH AXIS EXTENDING FROM 17N23W TO 08N24W AND MOVING WEST NEAR 15 KT. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED WITHIN A MODERATE MOIST ENVIRONMENT...WHICH ALONG WITH MIDDLE- LEVEL DIFFLUENCE SUPPORT SCATTERED MODERATE CONVECTION WITHIN 120 NM OF ITS AXIS. THIS WAVE IS FORECAST TO MERGE WITH THE LOW PRESSURE CENTER AHEAD OF IT TONIGHT...STRENGHTENING IT. A TROPICAL WAVE IS ON THE CENTRAL ATLC WITH AXIS EXTENDING FROM 19N40W TO 10N40W AND MOVING W NEAR 10 KT. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS MOSTLY EMBEDDED WITHIN A DRY ENVIRONMENT. THE WAVE IS EAST OF THE BASE OF AN UPPER-LEVEL TROUGH. STRONG SOUTHWESTERLY FLOW ASSOCIATED WITH THE UPPER-LEVEL TROUGH IS KEEPING THE CONVECTION ASSOCIATED WITH THE WAVE NE OF THE AXIS...CONFINED TO A SMALL AREA OF MAXIMUM MOISTURE IN THE SSMI TPW IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 16N-21N BETWEEN 35W-39W BEING SUPPORTED BY MIDDLE-LEVEL DIFFLUENCE. A TROPICAL WAVE IS ON THE EASTERN CARIBBEAN WITH AXIS EXTENDING FROM 18N67W TO 10N67W AND MOVING W NEAR 5-10 KT. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED WITHIN A VERY MOIST ENVIRONMENT. HOWEVER...STRONG WESTERLY SHEAR IS HINDERING DEEP CONVECTION NEAR THE WAVE AXIS. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE WITHIN 190 NM E OF THE AXIS N OF 14N...INCLUDING PUERTO RICO AND WITHIN 100 NM W OF THE AXIS...INCLUDING THE MONA PASSAGE. DUE TO THE EASTERLY SHEAR MOST OF THE CONVECTION ASSOCIATED WITH THE WAVE LIES OVER THE LESSER ANTILLES AS SCATTERED MODERATE WITH ISOLATED TSTMS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 13N16W TO THE 1012 MB SPECIAL FEATURES LOW NEAR 09N27W TO 08N32W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N32W TO 07N43W TO 05N52W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE AND THE LOW PRESSURE CENTER...SCATTERED MODERATE CONVECTION IS FROM 03N-10N E OF 19W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM THE MIDDLE ATLC STATES SW TO THE BAY OF CAMPECHE IN THE GULF. THIS TROUGH IS SUPPORTING A 1009 MB LOW PRESSURE CENTER OFFSHORE JACKSONVILLE NEAR 30N80W FROM WHICH A COLD FRONT EXTENDS SW ACROSS CENTRAL- SOUTHERN FLORIDA TO 25N81W TO 21N88W JUST NORTH OF THE YUCATAN PENINSULA TO INLAND MEXICO NEAR 17N94W. SCATTERED MODERATE CONVECTION IS OVER THE BAY OF CAMPECHE S OF 21N E OF 96W...COINCIDING WITH A VERY MOIST ENVIRONMENT EVIDENCED IN THE SSMI TOTAL PRECIPITABLE WATER IMAGERY AS WELL AS WATER VAPOR IMAGERY. ISOLATED SHOWERS ARE WITHIN 90 NM WEST OF THE COLD FRONT IN THE SE GULF. SUBSIDENCE OF VERY DRY AIR DOMINATES THE REMAINDER BASIN...THUS SUPPORTING FAIR WEATHER. THE COLD FRONT WILL CONTINUE CONTINUE TO MOVE E-SE WITHIN THE NEXT 24 HOURS AND IS FORECAST TO DISSIPATE BY WED NIGHT. THE CARIBBEAN SEA... A VERY MOIST REGION IS IN THE FAR NW CARIBBEAN COINCIDING WITH AN AREA OF UPPER-LEVEL DIFFLUENT FLOW FROM THE TROUGH COVERING THE GULF AND A WEAK UPPER-LEVEL RIDGE OVER NORTHERN CENTRAL AMERICA AND THE YUCATAN PENINSULA. THIS DIFFLUENT FLOW IS SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 13N-21N W OF 82W. SMALL CLUSTERS OF MODERATE CONVECTION WITH EMBEDDED TSTMS ARE OVER THE SOUTHERN GULF S OF 12N W OF 78W WHICH ARE ASSOCIATED WITH THE MONSOON TROUGH WHICH AXIS EXTENDS FROM NORTHERN COSTA RICA TO NORTHERN COLOMBIA. A TROPICAL WAVE IS ON THE EASTERN CARIBBEAN WITH AXIS EXTENDING FROM 18N67W TO 10N67W. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED WITHIN A VERY MOIST ENVIRONMENT. HOWEVER...STRONG WESTERLY SHEAR IS HINDERING DEEP CONVECTION NEAR THE WAVE AXIS. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE WITHIN 190 NM E OF THE AXIS N OF 14N...INCLUDING PUERTO RICO AND WITHIN 100 NM W OF THE AXIS...INCLUDING THE MONA PASSAGE. DUE TO THE EASTERLY SHEAR MOST OF THE CONVECTION ASSOCIATED WITH THE WAVE LIES OVER THE LESSER ANTILLES AS SCATTERED MODERATE WITH ISOLATED TSTMS. THE TROPICAL WAVE IS FORECAST TO MOVE WESTWARD AND AFFECT HISPANIOLA WITH SHOWERS TONIGHT AND WED MORNING. THEN IT IS EXPECTED TO MOVE ACROSS CENTRAL AMERICA BY EARLY THURSDAY AFTERNOON. HISPANIOLA... EXCEPT FOR THE EASTERN DOMINICAN REPUBLIC WHERE SHOWERS AND TSTMS ASSOCIATED WITH THE TROPICAL WAVE ARE BEING REPORTED...MOSTLY CLEAR SKIES DOMINATES THE ISLAND. HOWEVER...AS THE AFTERNOON AND EVENING PROGRESS AND THE WAVE CONTINUES TO MOVE WESTWARD THE SHOWERS WILL EXTEND ACROSS THE ISLAND. PRECIPITATION ASSOCIATED WITH THE TROPICAL WAVE IS FORECAST TO LAST UNTIL WED MORNING. THE ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM THE MIDDLE ATLC STATES SW TO THE BAY OF CAMPECHE IN THE GULF. THIS TROUGH IS SUPPORTING A 1009 MB LOW PRESSURE CENTER OFFSHORE JACKSONVILLE NEAR 30N80W FROM WHICH A COLD FRONT EXTENDS SW TO MOSQUITO LAGOON AND THEN ACROSS CENTRAL-SOUTHERN FLORIDA TO 25N81W. A STATIONARY FRONT EXTENDS NORTHWARD FROM THE LOW WHICH CONNECTS TO A WARM FRONT N OF THE AREA OF DISCUSSION. SCATTERED SHOWERS AND ISOLATED TSTMS ARE N OF 25N BETWEEN 73W-80W...INCLUDING THE NORTHERN BAHAMAS. FARTHER EAST...AN UPPER-LEVEL LOW CENTERED NEAR 27N68W SUPPORTS A 1013 MB LOW NEAR 29N68W FROM WHICH A TROUGH EXTENDS ALONG 27N64W TO 24N62W. SCATTERED MODERATE CONVECTION IS FROM 25N-31N BETWEEN 58W-65W. OTHERWISE...A COLD FRONT ENTERS THE AREA OF DISCUSSION FROM 30N41W TO 30N50W WITH NO CONVECTION. 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