000 AXNT20 KNHC 120601 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU DEC 12 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE EAST TROPICAL ATLC NEAR 06N11W TO 06N16W. THE ITCZ AXIS EXTENDS FROM 06N16W TO 04N26W TO 03N37W TO 0N50W. SCATTERED MODERATE CONVECTION AND TSTMS ARE FROM 03N-06N BETWEEN 11W-19W. SCATTERED MODERATE CONVECTION IS FROM 02N-13N BETWEEN 20W-42W. SIMILAR CONVECTION IS WITHIN AN AREA ENCLOSED BY A LINE FROM 20N16W TO 12N28W AND A LINE EXTENDING FROM 21N19W TO 14N32W. ...DISCUSSION... GULF OF MEXICO... A BROAD MIDDLE-LEVEL TROUGH WITH AXIS EXTENDING FROM THE NE U.S.A CONUS TO THE CENTRAL GULF SUPPORTS A STATIONARY FRONT ANALYZED FROM WESTERN-CENTRAL FLORIDA NEAR 27N82W SW TO 24N90W TO THE BAY OF CAMPECHE NEAR 18N93W. A 1039 MB HIGH CENTERED IN THE MIDDLE MISSISSIPPI VALLEY NEAR 40N95W EXTENDS A RIDGE AXIS INTO THE GULF AND PROVIDES NORTHEASTERLY WIND FLOW UP TO 20 KT ACROSS THE ENTIRE BASIN. EXCEPT FOR THE FAR WESTERN BASIN W OF 95W S OF 25N AND THE SE GULF S OF 25N...SSMI TPW IMAGERY DEPICT DRY AIR ACROSS THE BASIN AT THE LOWER LEVELS WHICH IS SUSTAINING FAIR WEATHER. IN THE SE GULF...A SURFACE TROUGH OVER THE FAR NW CARIBBEAN SEA IS ADVECTING VERY MOIST AIR TO SUPPORT SCATTERED SHOWERS OVER THE FLORIDA STRAITS AND THE YUCATAN CHANNEL. HIGH PRESSURE AND NORTHEASTERLY WIND FLOW ARE EXPECTED TO CONTINUE ACROSS THE GULF THROUGHOUT FRIDAY MORNING. THE FRONTAL BOUNDARY IS FORECAST TO MOVE OUT OF THE GULF WATERS BY EARLY FRIDAY. CARIBBEAN SEA... LOW-LEVEL MOISTURE CONVERGENCE IS ALONG THE COASTLINE FROM THE YUCATAN PENINSULA TO NORTHERN COSTA RICA TO SUPPORT SCATTERED MODERATE CONVECTION WITHIN 120 NM OF THE COAST OF NICARAGUA AND NORTHERN COSTA RICA. SIMILAR CONVECTION IS S OF 22N W OF 82W ASSOCIATED WITH THE REMNANTS OF A SURFACE TROUGH THAT AT 0300 UTC EXTENDS FROM 20N86W TO NW HONDURAS NEAR 15N87W. OVER THE CENTRAL BASIN...AN UPPER-LEVEL LOW OVER HISPANIOLA SUPPORTS A SURFACE TROUGH ACROSS THE EASTERN ISLAND TO SOUTHERN ADJACENT WATERS NEAR 15N. THE SURFACE TROUGH IS GENERATING ISOLATED SHOWERS AND TSTMS ACROSS THE DOMINICAN REPUBLIC AND N OF 15N BETWEEN 68W-73W. ALOFT AND ACROSS THE REMAINDER BASIN WESTERLY WIND FLOW AND DRY AIR SUBSIDENCE DOMINATE AND SUPPORT FAIR WEATHER. OTHERWISE...A RELATIVELY TIGHT PRESSURE GRADIENT OVER THE CENTRAL-EASTERN BASIN SUPPORTS 20-25 KT WINDS EXPECTED TO PERSIST THROUGHOUT SAT MORNING. RAINSHOWERS ASSOCIATED WITH THE REMNANTS OF THE SURFACE TROUGH ARE EXPECTED THROUGHOUT THU NIGHT. HISPANIOLA... AN UPPER-LEVEL LOW OVER HISPANIOLA SUPPORTS A SURFACE TROUGH ACROSS THE EASTERN ISLAND TO SOUTHERN ADJACENT WATERS NEAR 15N. THE SURFACE TROUGH IS GENERATING ISOLATED SHOWERS AND TSTMS ACROSS THE DOMINICAN REPUBLIC AND N OF 15N BETWEEN 68W-73W. SHOWERS ASSOCIATED WITH THIS TROUGH WILL CONTINUE THROUGHOUT THU NIGHT. ATLANTIC OCEAN... A BROAD MIDDLE-LEVEL TROUGH WITH AXIS EXTENDING FROM THE NE U.S.A CONUS TO THE CENTRAL GULF SUPPORTS A STATIONARY FRONT ANALYZED FROM 30N67W SW TO THE EASTERN-CENTRAL FLORIDA COAST NEAR 27N80W. VERY DRY AIR ACROSS THE SW NORTH ATLC AND CENTRAL ATLC HINDERS CONVECTION AT THE TIME. FARTHER EAST OVER THE CENTRAL-EASTERN ATLC...A 1027 MB HIGH IS NEAR 28N40W WHICH IS EXPECTED TO DRIFT E OVER THE NEXT 24 HOURS MAINTAINING FAIR WEATHER CONDITIONS. A MIDDLE TO UPPER LEVEL NARROW TROUGH ALONG THE EASTERN ATLC SUPPORTS A FRONTAL SYSTEM ANALYZED AS A COLD FRONT FROM 30N15W TO 24N18W TO 21N22W. SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THIS FRONTAL SYSTEM ARE N OF 23N BETWEEN 13W-20W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR