000 AXNT20 KNHC 040557 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN JAN 04 2015 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 0545 UTC. ...SPECIAL FEATURES... ...GALE FORCE WINDS IN THE CARIBBEAN SEA... GALE FORCE WINDS PREVAIL ON THE SW CARIBBEAN FROM 11N TO 14N BETWEEN 73W AND 78W WITH SEAS RANGING FROM 14 TO 22 FT. THE GALE WARNING WILL CONTINUE THROUGH MONDAY NIGHT. ...GALE FORCE WINDS TO DEVELOP IN GULF OF MEXICO... A COLD FRONT EXTENDS A 1012 MB LOW ON NORTHERN MISSISSIPPI TO 29N90W 24N94W TO 21N97W. GALE FORCE WINDS ARE FORECAST TO DEVELOP SUNDAY AFTERNOON OVER THE W-SW GULF CONTINUING UNTIL MONDAY NIGHT. PLEASE REFER TO THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC AND THE OFFSHORE FORECAST UNDER AWIPS/WMO HEADERS MIAOFFNT3/FZNT23 KNHC FOR MORE DETAILS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA AND CONTINUES OVER THE FAR EASTERN ATLC TO 07N14W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 06N28W TO 01N42W. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE FROM 02N TO 12N BETWEEN 15W AND 39W. ...DISCUSSION... GULF OF MEXICO... A COLD FRONT IS OVER THE WESTERN BASIN EXTENDING SW FROM A 1012 MB LOW ON NORTHERN MISSISSIPPI TO 29N90W 24N94W TO 21N97W. THE FRONT COINCIDES WITH A DIFFLUENT ENVIRONMENT ALOFT BETWEEN A TROUGH OVER THE CENTRAL U.S. AND A RIDGE ANCHORED OVER THE CARIBBEAN WHICH ALONG WITH LOW-LEVEL MOISTURE CONVERGENCE ENHANCE SCATTERED SHOWERS WITHIN 200 NM EITHER SIDE OF THE FRONT AND TSTMS N OF 27N BETWEEN 88W-93W. SOUTHEASTERLY FLOW AHEAD OF THE FRONT CONTINUES TO ADVECT SHALLOW MOISTURE ACROSS THE WESTERN BASIN TO SUPPORT FOG N OF 27N W OF 90W. GALE FORCE WINDS ARE FORECAST TO DEVELOP ON THE W-SW GULF SUNDAY NIGHT. SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. THE COLD FRONT WILL EXTEND FROM CENTRAL FLORIDA SW TO THE BAY OF CAMPECHE ON MONDAY MORNING AND THEN WILL STALL THROUGH TUE MORNING. CARIBBEAN SEA... A PERSISTENT AND BROAD UPPER LEVEL RIDGE CENTERED OVER THE NW CARIBBEAN IS PRODUCING SUBSIDENCE THAT IS INHIBITING DEEP CONVECTION OVER THE ENTIRE CARIBBEAN BASIN. SHALLOW MOISTURE IN THE TRADE WIND FLOW IS PRODUCING ISOLATED WEAK SHOWERS ACROSS THE CENTRAL AND EASTERN CARIBBEAN AND SURROUNDING ISLANDS. A STRONG PRESSURE GRADIENT BETWEEN WESTERN ATLANTIC HIGH PRESSURE AND LOW PRESSURE ACROSS CENTRAL AND SOUTHERN AMERICA IS PRODUCING GALE FORCE WINDS OVER THE SW CARIBBEAN. SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE DETAILS. TRADE WINDS OF 20 TO 25 KT ARE ELSEWHERE IN THE CARIBBEAN. HISPANIOLA... AN OVERALL STABLE ENVIRONMENT PREVAILS AS AN UPPER-LEVEL ANTICYCLONE CONTINUES ACROSS THE CARIBBEAN SUPPORTING SUBSIDENCE. HOWEVER...SHALLOW MOISTURE TRANSPORTED BY THE TRADE WIND FLOW MAY ENHANCE ISOLATED SHOWERS ACROSS THE ISLAND TONIGHT. A SIMILAR PATTERN IS EXPECTED THROUGH SUNDAY. ATLANTIC OCEAN... SURFACE HIGH PRESSURE IS ACROSS GREAT PORTIONS OF THE BASIN N OF 10N...EXCEPT N OF 28N BETWEEN 36W-48W WHERE THE TAIL OF A SURFACE TROUGH EXTENDS FROM 31N45W TO 29N48W. NO DEEP CONVECTION IS ASSOCIATED WITH THIS TROUGH IN THE AREA OF DISCUSSION. HIGH PRESSURE OVER THE W ATLANTIC WILL PERSIST WHILE SLOWLY SHIFTING EAST OVER THE NEXT COUPLE OF DAYS. A COLD FRONT WILL EXIT THE SE CONUS COAST ENTERING THE WESTERN ATLANTIC SUNDAY NIGHT WITH CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR