000 AXNT20 KNHC 230557 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST MON DEC 23 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 FEATURES... AS OF 0300 UTC...AN INITIAL COLD FRONT EXTENDS FROM NEAR PANAMA CITY BEACH FLORIDA TO 23N95W TO THE MEXICAN COAST NEAR 19N95W. A SECONDARY AND STRONGER FRONT EXTENDS FROM JUST E OF LAFAYETTE LOUISIANA TO ABOUT 60 NM S OF BROWNSVILLE TEXAS. THIS SECONDARY FRONT HAS USHERED IN WINDS OF GALE FORCE...WITH WINDS OF 35 KT LIKELY OCCURRING OVER THE FAR WESTERN GULF. A 0302 UTC ASCAT-B PASS HAS INDICATED WINDS OF 30 KT OR GREATER WITHIN 90 NM NW OF THE SECONDARY FRONT AND S OF 26N. GALE FORCE NORTHERLY WINDS OF 30-40 KT ARE EXPECTED TO PERSIST UNTIL LATE TUE MAINLY S OF 22N W OF 95W. PLEASE REFER TO THE LATEST NHC/TAFB HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM THE AFRICAN COAST NEAR 5N9W TO 4N30W TO 2N40W TO THE COAST OF SOUTH AMERICA NEAR 0N47W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM OF THE AXIS BETWEEN 23W-31W...AND IN AN AREA FROM THE EQUATOR TO 6N BETWEEN 38W-46W. ...DISCUSSION... GULF OF MEXICO... AS OF 0300 UTC...AN INITIAL COLD FRONT EXTENDS FROM NEAR PANAMA CITY BEACH FLORIDA TO 23N95W TO THE MEXICAN COAST NEAR 19N95W. A SECONDARY AND STRONGER FRONT EXTENDS FROM JUST E OF LAFAYETTE LOUISIANA TO ABOUT 60 NM S OF BROWNSVILLE TEXAS. THIS SECONDARY FRONT HAS USHERED IN WINDS APPROACHING GALE FORCE WITH MOST BUOYS REPORTING WINDS OF 25 TO 30 KT AND SEAS BUILDING TO 11 FT. SOUTHERLY WINDS OF 15 TO 20 KT ARE OCCURRING OVER THE GULF N OF 27N E OF THE FRONT. COASTAL WSR-88D RADAR DATA SHOWS SCATTERED SHOWERS AND THUNDERSTORMS BETWEEN THE TWO FRONTAL BOUNDARIES WITH THE BULK OF THE ACTIVITY OCCURRING BETWEEN PANAMA CITY FLORIDA AND THE SOUTH-CENTRAL COAST OF LOUISIANA. FAIR SKIES PREVAIL ELSEWHERE OVER THE GULF SE OF THE FIRST FRONT. IN THE UPPER LEVELS...BROAD SW FLOW COVERS THE ENTIRE GULF BETWEEN AN ELONGATED ANTICYCLONE OVER THE SW N ATLC AND A SHARP TROUGH OVER THE GREAT PLAINS. THE SW FLOW ALOFT WAS ADVECTING DEEP TROPICAL MOISTURE WITHIN A NARROW 300 NM WIDE BAND TOWARD THE N-CENTRAL GULF COAST. CARIBBEAN SEA... A 0258 UTC ASCAT-B PASS INDICATED A BROAD SWATH OF 25-30 KT TRADE WINDS OVER THE CARIBBEAN FROM 10N-16N BETWEEN 72W-78W WITH THE HIGHEST WINDS...30 KT...WITHIN 90 NM OF THE COAST OF COLOMBIA. 15-20 KT TRADEWINDS WERE NOTED OVER THE REMAINDER OF THE CARIBBEAN SEA. SCATTERED LOW TOPPED SHOWERS ARE OVER HONDURAS...NICARAGUA...AND COSTA RICA. MORE SCATTERED SHOWERS ARE OVER HISPANIOLA... PUERTO RICO...AND THE LEEWARD ISLANDS. IN THE UPPER LEVELS...A LARGE UPPER LOW OVER THE TROPICAL ATLC NEAR 22N60W WAS EXPANDING ITS INFLUENCE OVER THE CARIBBEAN E OF 73W WHILE A NARROW RIDGE PREVAILED OVER THE BASIN BETWEEN 73W AND 85W. STRONG SUBSIDENCE DOMINATED THE CARIBBEAN WHILE UPPER LEVEL MOISTURE WAS ON THE INCREASE OVER THE FAR NE CARIBBEAN AND LEEWARD ISLANDS. THE UPPER LEVEL LOW IS FORECAST TO MOVE W IN TANDEM WITH A SURFACE TROUGH OVER PUERTO RICO IN THE NEXT 24 HOURS WITH AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY OVER THE E CARIBBEAN AND THE NORTHERN LEEWARD ISLANDS. ...HISPANIOLA... SCATTERED WARM TOP SHOWERS ARE SWEEPING OVER THE HIGHER ELEVATIONS OF HISPANIOLA. IN THE UPPER LEVELS...VERY STRONG SUBSIDENCE IS SUPPRESSING THUNDERSTORM ACTIVITY. ONCE AGAIN THIS WAS REFLECTED IN VERY DRY AIR ABOVE 600 MB IN THE 00Z SAN JUAN RAOB. LITTLE CHANGE IN OVERALL CONDITIONS EXPECTED TODAY...HOWEVER THE PROXIMITY OF A LARGE UPPER LOW AND A SURFACE TROUGH OVER PUERTO RICO MAY RESULT IN SOME ADDITIONAL ACTIVITY MON NIGHT AND TUE. ATLANTIC OCEAN... A STATIONARY 1034 MB HIGH IS CENTERED OVER THE W ATLANTIC NEAR 35N51W PRODUCING FAIR WEATHER OVER THE BAHAMAS AND W ATLANTIC. ASSOCIATED RIDGE EXTENDS EASTWARD OVER THE SUBTROPICAL ATLC ALONG 31N TO THE NW COAST OF AFRICA. IN THE TROPICS...A SURFACE TROUGH IS E OF THE LESSER ANTILLES FROM 18N56W TO 11N55W MOVING W. SCATTERED SHOWERS ARE WITHIN 120 NM OF THE TROUGH AXIS. OF NOTE IN THE UPPER LEVELS...A LARGE UPPER LEVEL LOW IS CENTERED NE OF THE LESSER ANTILLES NEAR 22N60W ENHANCING SHOWERS. ELSEWHERE...UPPER LEVEL DIFFLUENCE OVER THE CANARY ISLANDS ARE ENHANCING SHOWERS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB