000 AXNT20 KNHC 131153 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI DEC 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE EAST TROPICAL ATLC NEAR 09N13W TO 07N17W. THE ITCZ AXIS EXTENDS FROM 07N17W TO 03N28W TO 03N42W. ISOLATED SHOWERS ARE WITHIN 70 NM BETWEEN 22W-37W. ...DISCUSSION... GULF OF MEXICO... A BROAD MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING ALONG THE NORTHWESTERN ATLC SUPPORTS A FRONTAL SYSTEM ANALYZED AS A STATIONARY FRONT FROM THE FLORIDA STRAITS NEAR 24N80W SW TO THE NE YUCATAN PENINSULA NEAR 21N87W. RADAR AND SATELLITE IMAGERY CONTINUE TO SHOW ISOLATED SHOWERS OVER THIS REGION OF THE SE GULF. A 1032 MB HIGH CENTERED OVER SE TENNESSEE NEAR 35N85W EXTENDS A RIDGE INTO THE GULF AND PROVIDES NORTHEASTERLY WIND FLOW UP TO 20 KT ACROSS THE BASIN. SSMI TPW IMAGERY DEPICT AN ARCTIC AIRMASS PUSHING INTO THE NE GULF AND ALSO VERY DRY AIR ACROSS THE REMAINDER BASIN WHICH IS SUPPORTING FAIR WEATHER. IN THE UPPER-LEVEL...SOUTHWESTERLY WIND FLOW ADVECTS MOISTURE FROM THE EPAC ITCZ REGION TO SUPPORT BROKEN TO OVERCAST SKIES ACROSS THE NORTHERN GULF N OF 27N W OF 87W. HIGH PRESSURE AND NORTHEASTERLY WIND FLOW ARE EXPECTED TO CONTINUE ACROSS THE GULF THROUGHOUT FRI MORNING. RETURN FLOW STARTS TO BUILD ACROSS THE GULF FRI AFTERNOON AS THE HIGH PRESSURE CENTER MOVES TO NW ATLC WATERS NEAR THE COAST OF NORTH CAROLINA. THE PORTION OF THE FRONTAL BOUNDARY ACROSS THE SE GULF IS FORECAST TO DISSIPATE EARLY FRI. A NEW COLD FRONT IS FORECAST TO EMERGE ACROSS THE NW GULF SAT AFTERNOON. CARIBBEAN SEA... LOW-LEVEL MOISTURE CONVERGENCE IS ALONG THE COASTLINE FROM THE YUCATAN PENINSULA TO CENTRAL PANAMA TO SUPPORT SCATTERED MODERATE CONVECTION WITHIN 100 NM FROM THE COAST. OVER THE CENTRAL BASIN...A MIDDLE-LEVEL LOW CENTERED NEAR 11N76W SUPPORTS A SURFACE TROUGH FROM EASTERN CUBA NEAR 20N74W TO NORTHERN COLOMBIA NEAR 10N75W. ISOLATED SHOWERS ASSOCIATED WITH THE TROUGH ARE N OF 17N BETWEEN 72W-77W...INCLUDING THE WINDWARD PASSAGE AND JAMAICA. MIDDLE-LEVEL DIFFLUENCE GENERATED BY THE LOW S OF THE CENTRAL CARIBBEAN AND THE SW PERIPHERY OF A BROAD ANTICYCLONIC CIRCULATION OVER THE CENTRAL ATLC SUPPORTS ISOLATED SHOWERS AND TSTMS N OF 13N BETWEEN 65W-69W. ACROSS THE REMAINDER BASIN DRY AIR SUBSIDENCE FROM THE MIDDLE LEVELS DOMINATE TO 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. HISPANIOLA... A MIDDLE-LEVEL LOW CENTERED NEAR 11N76W SUPPORTS A SURFACE TROUGH FROM EASTERN CUBA NEAR 20N74W TO NORTHERN COLOMBIA NEAR 10N75W. ISOLATED SHOWERS ASSOCIATED WITH THE TROUGH ARE N OF 17N BETWEEN 72W-77W...INCLUDING THE WINDWARD PASSAGE AND HAITI. WHILE THE TROUGH CONTINUES TO MOVE WESTWARD THIS MORNING A DRY AIRMASS MOVES ACROSS THE ISLAND TO SUPPORT FAIR WEATHER THROUGHOUT SAT AFTERNOON. ATLANTIC OCEAN... A BROAD MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING ALONG THE NORTHWESTERN ATLC SUPPORTS A FRONTAL SYSTEM ANALYZED AS A COLD FRONT FROM 30N61W SW TO 27N68W TO 25N73W WHERE IT TRANSITIONS TO A STATIONARY FRONT TO THE FLORIDA STRAITS. VERY DRY AIR ACROSS THE SW NORTH ATLC AND CENTRAL ATLC HINDERS CONVECTION AT THE TIME. FARTHER EAST OVER THE CENTRAL ATLC...A 1027 MB HIGH IS NEAR 29N37W WHICH IS EXPECTED TO DRIFT NE OVER THE NEXT 24 HOURS MAINTAINING FAIR WEATHER CONDITIONS ACROSS MOST OF THE ATLC. A WEAK SURFACE TROUGH IS FARTHER EAST WEST OF THE CANARY ISLANDS ALONG 31N20W TO 22N20W WITH NO CONVECTION ASSOCIATED WITH IT AT THE TIME. OTHERWISE...AN AREA OF SCATTERED SHOWERS IS LOCATED FROM 11N-18N E OF 34W...INCLUDING THE CAPE VERDE ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR