000 AXNT20 KNHC 051153 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST THU MAR 05 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1130 UTC. ...SPECIAL FEATURES... ...GALE WARNING FOR THE SW CARIBBEAN... A GALE WARNING IS IN EFFECT FOR COASTAL WATERS OF COLOMBIA FROM 10.5N TO 13.5N BETWEEN 74W AND 77W WITH SEAS RANGING BETWEEN 10 AND 15 FT. THESE CONDITIONS ARE FORECAST THROUGH THURSDAY AFTERNOON...RESUMING AGAIN DURING THE NIGHT HOURS. PLEASE SEE THE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ FZNT02 KNHC FOR MORE DETAILS. ...GALE WARNING FOR THE GULF OF MEXICO... A GALE WARNING IS IN EFFECT FOR THE NW GULF ASSOCIATED WITH A COLD FRONT THAT MOVED OFF THE LOUISIANA AND TEXAS COAST THIS MORNING. GALE CONDITIONS ARE FORECAST TO CONTINUE W OF THE FRONT UNTIL FRIDAY NIGHT...AS THE FRONT MOVES E-SE. PLEASE SEE THE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLANTIC NEAR 05N09W TO 04N13W WHERE THE ITCZ BEGINS AND CONTINUES ALONG THE EQUATOR TO 30W THEN TO THE COAST OF NORTHERN BRAZIL NEAR 01S50W. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE FROM THE EQUATOR TO 06S BETWEEN 12W AND 34W...AND FROM THE EQUATOR TO 06N W OF 42W. ...DISCUSSION... GULF OF MEXICO... A BROAD RIDGE ANCHORED OVER THE CENTRAL ATLC N OF 30N CONTINUES TO EXTEND AN AXIS SW ACROSS THE FLORIDA PENINSULA AND THE EASTERN GULF. SURFACE LOW PRESSURE IS BUILDING OVER THE WESTERN BASIN ASSOCIATED WITH A COLD FRONT THAT CAME OFF THE LOUISIANA AND TEXAS COASTS THIS MORNING. THE COLD FRONT EXTENDS FROM 29N92W SW TO NE MEXICO NEAR 25N97W WITH GALE FORCE WINDS W OF THE BOUNDARY. SE TO S WIND FLOW OF 10 TO 15 KT IS ELSEWHERE E OF THE COLD FRONT. ALOFT...SOUTHWESTERLY FLOW COVERS THE BASIN WITH WATER VAPOR IMAGERY INDICATING RELATIVELY STRONG SUBSIDENCE...EXCEPT FOR THE NW GULF WHERE MOISTURE IS BEING ADVECTED FROM THE EPAC WATERS. OVERALL STABLE CONDITIONS ALOFT AND AT THE SURFACE E OF THE FRONT FAVOR FAIR WEATHER AND CLEAR SKIES DOMINATE. OVER THE NW GULF...LOW-LEVEL MOISTURE CONVERGENCE AND A DIFFLUENT ENVIRONMENT ALOFT ASSOCIATED WITH THE COLD FRONT SUPPORT BROKEN TO OVERCAST SKIES WITH POSSIBLE ISOLATED SHOWERS. IN ADDITION...FOG AND HAZE IS BEING REPORTED N OF 25N W OF 90W AND OVER THE FLORIDA PANHANDLE...COINCIDING WITH MEDIUM TO HIGH GOES-13 IFR PROBABILITIES OF FOG. THE COLD FRONT WILL EXTEND FROM THE FLORIDA PANHANDLE SW TO THE BAY OF CAMPECHE TONIGHT AND WILL START DISSIPATING OVER CENTRAL FLORIDA FRIDAY NIGHT. GALE FORCE WINDS ARE FORECAST TO CONTINUE W OF THE FRONT THROUGH FRIDAY NIGHT. SEE SPECIAL FEATURES ABOVE. CARIBBEAN SEA... BROAD UPPER LEVEL TROUGHING IS OBSERVED ON WATER VAPOR IMAGERY COVERING THE CENTRAL AND EASTERN CARIBBEAN WHILE A RIDGE COVERS THE REMAINDER BASIN. RELATIVELY DRY AND STABLE AIR IS ASSOCIATED WITH THIS UPPER WIND PATTERN WHICH CONTINUE TO PROVIDE OVERALL FAIR CONDITIONS ACROSS THE BASIN. AT THE LOWER LEVELS...MOISTURE PATCHES ARE OBSERVED MAINLY S OF 15N AND OVER THE NW CARIBBEAN...POSSIBLY ENHANCING ISOLATED SHOWERS. A SHALLOW AIRMASS IS ALSO OBSERVED MOVING ACROSS PUERTO RICO AND ADJACENT WATERS INCREASING THE CHANCE OF ISOLATED SHOWERS DURING THE MORNING AND AFTERNOON HOURS. TRADE WINDS OF 20 TO 25 KT ARE OVER THE EASTERN AND CENTRAL BASIN...INCREASING TO GALE FORCE WINDS ALONG THE COAST OF COLOMBIA. PLEASE SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE DETAILS. TRADES OF 15 KT ARE ELSEWHERE. ...HISPANIOLA... DEEP LAYER DRY AIR IS OVER HISPANIOLA AND IS EXPECTED TO PREVAIL THROUGHOUT SUNDAY MORNING THUS FAVORING FAIR WEATHER CONDITIONS. ATLANTIC OCEAN... A NARROW UPPER LEVEL TROUGH OVER THE CENTRAL ATLC EXTENDING SW TO A BASE OVER THE SW CARIBBEAN CONTINUE TO SUPPORT A FRONT ANALYZED AS A DISSIPATING COLD FRONT FROM 30N41W SW TO 26N49W. NO CONVECTION IS ASSOCIATED WITH IT. OTHERWISE...THE REMAINDER ATLC W AND E OF THE FRONTAL BOUNDARY IS UNDER THE INFLUENCE OF A BROAD SURFACE RIDGE ANCHORED BY A PAIR OF HIGH PRESSURE CENTERS N OF THE AREA OF DISCUSSION. THE NEXT COLD FRONT ENTERS THE SW N ATLC WATERS FRIDAY MORNING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR