000 AXNT20 KNHC 121747 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED MAR 12 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... A COLD FRONT EXTENDS FROM THE SOUTHWESTERN LOUISIANA COAST NEAR 30N93W SW TO THE TEXAS COAST NEAR 27N97W THAT IS PRODUCING STRONG NORTHERLY WINDS WITH FREQUENT GUSTS TO GALE FORCE ACROSS THE GULF WATERS NW OF THE FRONT THIS AFTERNOON. THE FRONT IS FORECAST TO SWEEP SOUTHEASTWARD THROUGH THURSDAY WITH GALE FORCE WINDS EXPECTED BY 13/0000 UTC. IN ADDITION...AS THE FRONT MOVES INTO THE SW NORTH ATLC...NW GALE FORCE WINDS ARE EXPECTED N OF 30N WEST OF THE FRONT BEGINNING AT 13/0600 UTC. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N11W TO 02N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 02N16W TO THE EQUATOR AT 20W. ISOLATED MODERATE CONVECTION IS S OF 04N BETWEEN 12W-19W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY EXITING THE REGION TO THE NORTHEAST OVER NORTHERN FLORIDA AND INTO PORTIONS OF THE SW NORTH ATLC THIS AFTERNOON. A WEAKENING SURFACE TROUGH IS ANALYZED WEST OF THE UPPER LEVEL DYNAMICS FROM THE FLORIDA PANHANDLE NEAR 30N84W SW TO 26N90W WITH LOW-LEVEL MOISTURE CONVERGENCE REMAINING RELATIVELY LIMITED AT THIS TIME. MOST OF THE CLOUDINESS AND ISOLATED SHOWERS AND TSTMS ARE OCCURRING N OF 24N E OF 88W AS THE SYSTEM EXITS TO THE NORTHEAST THROUGH THIS EVENING. TO THE WEST HOWEVER...A STRONG COLD FRONT HAS EMERGED OFF THE TEXAS AND LOUISIANA COAST THIS MORNING AND IS CURRENTLY ANALYZED FROM 30N93W SW TO 27N97W. THE FRONT EXHIBITS LITTLE PRECIPITATION...BUT IS PRODUCING STRONG NORTHERLY WINDS IN ITS WAKE WITH THE HIGH PROBABILITY OF FREQUENT GUSTS TO GALE FORCE. AS THE FRONT SWEEPS SOUTHEASTWARD THROUGH THURSDAY...N-NE WINDS ARE FORECAST TO REMAIN IN THE 20 TO 30 KT RANGE...GRADUALLY DIMINISHING LATE THURSDAY INTO FRIDAY AS HIGH PRESSURE BUILDS INTO THE BASIN FROM THE SOUTHERN PLAINS. THE HIGH WILL SHIFT EASTWARD ALONG 30N/31N FRIDAY INTO SATURDAY WITH SOUTHERLY RETURN FLOW ONCE AGAIN RE-ESTABLISHING ITSELF ACROSS PORTIONS OF THE WESTERN GULF. CARIBBEAN SEA... OVERALL CONDITIONS ACROSS THE CARIBBEAN THIS AFTERNOON REMAIN RELATIVELY TRANQUIL AS UPPER LEVEL RIDGING IS ANCHORED OVER THE CARIBBEAN WITH AXIS EXTENDING FROM NORTHEAST VENEZUELA NEAR 09N63W NW TO 18N78W. THE UPPER LEVEL RIDGE IS GENERALLY PROVIDING STABILITY AND DRY AIR OVER THE BASIN RESULTING IN A LACK OF ANY SIGNIFICANT CONVECTION. A FEW ISOLATED SHOWERS ARE OCCURRING...WITH THE MOST CONCENTRATED AREA OF SHOWERS NOTED S OF 16N E OF 66W...INCLUDING THE WINDWARD ISLANDS. WINDS AT THE SURFACE ARE RELATIVELY WEAK ACROSS THE CARIBBEAN ON THE SOUTHWESTERN PERIPHERY OF A SURFACE RIDGE ANCHORED ACROSS THE CENTRAL ATLC. THE RIDGING TO THE NORTHEAST OF THE BASIN IS FORECAST TO CONTINUE SHIFTING E-NE AHEAD OF A COLD FRONT EXPECTED TO MOVE INTO THE NW CARIBBEAN EARLY THURSDAY. OTHERWISE...FAIR WEATHER CONDITIONS SHOULD REMAIN RELATIVELY UNCHANGED FOR THE NEXT FEW DAYS. ...HISPANIOLA... CURRENTLY MOSTLY CLEAR SKIES AND FAIR CONDITIONS ARE NOTED ON VISIBLE SATELLITE IMAGERY ACROSS THE ISLAND THIS AFTERNOON. HIGH PRESSURE REMAINS ANCHORED TO THE NORTHEAST ACROSS THE CENTRAL ATLC GENERATING LIGHT E-SE WINDS. THE RIDGING ACROSS THE REGION WILL SLIDE EAST THROUGH EARLY THURSDAY AS A FRONTAL BOUNDARY MOVES ACROSS THE SW NORTH ATLC WATERS AND BEGINS TO IMPACT HISPANIOLA LATE FRIDAY INTO SATURDAY WITH A HIGHER PROBABILITY OF PRECIPITATION AND STRONG NORTHEAST WINDS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE IS NOTED ON WATER VAPOR IMAGERY WITH ENERGY FOCUSED IN THE VICINITY OF 31N81W THAT IS GENERATING ISOLATED SHOWERS AND TSTMS N OF 28N W OF 70W THIS AFTERNOON AHEAD OF A COLD FRONT FORECAST TO ENTER THE REGION OVERNIGHT INTO THURSDAY. WINDS ARE EXPECTED TO SHIFT W-NW WITH GALE FORCE WINDS DEVELOPING BY 13/0600 UTC. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 30N54W. FARTHER EAST ACROSS THE CENTRAL ATLC...ANOTHER MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED NEAR 38N37W WITH AN UPPER LEVEL TROUGH AXIS EXTENDING SW TO 21N50W. THE TROUGHING SUPPORTS A COLD FRONT ANALYZED INTO THE DISCUSSION AREA NEAR 32N35W EXTENDING SW TO 28N41W AND BECOMING STATIONARY TO 20N55W. WIDELY SCATTERED SHOWERS AND TSTMS ARE OCCURRING 150 NM EAST OF THE COLD FRONT AND FROM 21N TO THE STATIONARY FRONT BETWEEN 36W-55W. OTHERWISE...THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE WITH AXIS EXTENDING FROM 32N26W S-SW TO 10N32W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN