000 AXNT20 KNHC 110557 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST WED DEC 11 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. ...SPECIAL FEATURE... GALE WARNING CURRENTLY IN EFFECT FOR THE GULF OF MEXICO S OF 22N W OF 95W IN ASSOCIATION WITH A COLD FRONT THAT AT 11/0300 UTC EXTENDS FROM 28N83W TO 22N94W TO 18N94W. SEE LATEST NHC HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE EAST TROPICAL ATLC NEAR 09N13W TO 07N18W. THE ITCZ AXIS EXTENDS FROM 07N18W TO 04N30W TO 02N40W. SCATTERED MODERATE CONVECTION IS MAINLY N OF THE AXES FROM 11N-20N E OF 28W...FROM 05N-11N BETWEEN 28W-46W AND FROM 01N-06N BETWEEN 27W-32W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL BROAD TROUGH WITH AXIS EXTENDING FROM MAINE SW TO CENTRAL FLORIDA SUPPORTS A COLD FRONT ANALYZED FROM WESTERN-CENTRAL FLORIDA NEAR 27N82W SW TO 23N90W TO THE BAY OF CAMPECHE NEAR 18N93W. A HIGH PRESSURE SYSTEM ACROSS THE LOWER MISSISSIPPI VALLEY AND EASTERN SOUTHERN PLAINS EXTENDS A RIDGE AXIS INTO THE GULF AND SUPPLIES NORTHEASTERLY WIND FLOW TO THE BASIN. A TIGHT PRESSURE GRADIENT BEHIND THE COLD FRONT IN THE SW GULF SUPPORT GALE FORCE WINDS THAT ARE FORECAST TO SUBSIDE AT 11/0600 UTC. SEE SPECIAL FEATURES SECTION FOR MORE DETAILS. SSMI TPW IMAGERY DEPICT DRY AIR OVER THE BASIN WHICH IS SUSTAINING FAIR WEATHER. WITHIN 24 HOURS...THE PORTION OF THE COLD FRONT OVER THE GULF IS FORECAST TO STALL AND SLOWLY DISSIPATE. HIGH PRESSURE AND NORTHEASTERLY WIND FLOW ARE EXPECTED TO CONTINUE ACROSS THE GULF THROUGHOUT FRIDAY MORNING. CARIBBEAN SEA... A MIDDLE-LEVEL INVERTED TROUGH WEST OF 72W CONTINUES TO SUPPORT A SURFACE TROUGH ANALYZED FROM 20N83W TO 14N83W. LOW-LEVEL MOISTURE CONVERGENCE ALONG THE TROUGH AXIS AND UPPER-LEVEL DIVERGENCE SUPPORT SCATTERED RAINSHOWERS AND ISOLATED TSTMS FROM 14N-21N BETWEEN 78W-86W. ALOFT AND ACROSS THE REMAINDER BASIN WESTERLY WIND FLOW AND DRY AIR SUBSIDENCE DOMINATE. SSMI TPW IMAGERY SHOW ADVECTION OF VERY DRY AIR FROM THE CENTRAL ATLC ACROSS THE EASTERN BASIN WHICH ALONG WITH MIDDLE LEVEL DRY AIR SUPPORT FAIR WEATHER. OTHERWISE...A RELATIVELY TIGHT PRESSURE GRADIENT OVER THE CENTRAL-EASTERN BASIN SUPPORTS 20-25 KT WINDS EXPECTED TO PERSIST THROUGHOUT FRI MORNING. THE SURFACE TROUGH WILL CONTINUE A WESTWARD TRACK AND IS FORECAST TO MOVE ACROSS CENTRAL AMERICA BY WED AFTERNOON. HISPANIOLA... FAIR WEATHER DOMINATES ACROSS THE ISLAND BEING SUPPORTED BY DRY AIR SUBSIDENCE FROM THE MIDDLE LEVELS AS WELL AS DRY AIR ADVECTION FROM THE NORTH-CENTRAL ATLC. FAIR WEATHER IS EXPECTED TO PERSIST THROUGHOUT FRI MORNING AS MULTI-LAYERED DRY AIR WILL CONTINUE TO MOVE ACROSS THE ISLAND. HOWEVER...AFTERNOON/EARLY EVENING SHOWERS ARE LIKELY WITHIN THAT TIME FRAME. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL BROAD TROUGH WITH AXIS EXTENDING FROM MAINE SW TO CENTRAL FLORIDA SUPPORTS A COLD FRONT ANALYZED FROM 30N75W SW TO EASTERN-CENTRAL FLORIDA NEAR 27N80W. VERY DRY AIR ACROSS THE SW NORTH ATLC HINDERS CONVECTION AT THE TIME. FARTHER EAST AND OVER THE CENTRAL ATLC...A 1027 MB HIGH IS NEAR 30N52W WHICH IS EXPECTED TO DRIFT SE OVER THE NEXT 24 HOURS MAINTAINING FAIR WEATHER CONDITIONS. A MIDDLE TO UPPER LEVEL TROUGH ACROSS THE EASTERN ATLC SUPPORTS A COLD FRONT ANALYZED FROM 30N20W TO 22N31W TO 20N44W. FARTHER EAST...THE SAME TROUGH ALOFT SUPPORTS A SURFACE TROUGH EXTENDING ALONG 30N18W TO 20N24W. SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THIS LOW PRESSURE SYSTEM ARE N OF 24N BETWEEN 13W-20W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR