000 AXNT20 KNHC 201031 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU MAR 20 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0915 UTC. ...SPECIAL FEATURE... CARIBBEAN GALE WARNING...STRONG HIGH PRES N OF THE AREA IS ENHANCING TRADE WIND FLOW OVER THE S CENTRAL CARIBBEAN. WINDS ARE ALREADY REACHING 30 KT OFF THE COAST OF COLOMBIA...AS NOTED DRAINAGE EFFECTS OFF THE HIGH TERRAIN ALONG THE COAST OF COLOMBIA WILL ALLOW THESE WINDS TO INCREASE TO GALE FORCE OVERNIGHT INTO THE EARLY MORNING HOURS. PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA AND CROSSES INTO THE TROPICAL ATLC NEAR ALONG THE COAST OF GUINEA NEAR 11N14W AND CONTINUES TO 05N17W AND THEN TO 03N20W WHERE THE ITCZ BEGINS. THE ITCZ CONTINUES SOUTHWEST TO 04S38W ALONG THE COAST OF BRAZIL. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION ARE NOTED WITHIN 60 NM OF THE ITCZ AND MONSOON TROUGH AXES BETWEEN 15W AND 23W...AND BETWEEN 30W AND 35W. ...DISCUSSION... GULF OF MEXICO... A WEAK COLD FRONT EXTENDS FROM THE TENNESSEE VALLEY TO LOUISIANA...THEN REMAINS STATIONARY ALONG THE TEXAS COAST. THE COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE DEEP SOUTH STATES TODAY FOLLOWED BY HIGH PRES BUILDING OVER THE LOWER MISSISSIPPI VALLEY...BUT SOUTHERN STATIONARY PORTION OF THE FRONT WILL WILL WASH OUT OVER THE NW GULF LATER THIS MORNING. PLATFORM OBSERVATIONS IN THE NW AND N CENTRAL GULF INDICATE SCATTERED TO OCCASIONALLY BROKEN CLOUD COVER WITH CEILINGS GREATER THAN 4K FT. WARM AND MOIST AIR FLOW ACROSS THE FRONT IS SUSTAINING THE DEVELOPMENT OF A FEW SHOWERS NEAR THE MOUTH OF THE RIO GRANDE. WEAK RIDGING AHEAD OF THE FRONT OVER THE NE GULF IS MAINTAINING FAIRLY LIGHT WINDS ACROSS THE NORTHERN GULF WATERS. A WEAK TROUGH IS NOTED OVER THE SW GULF...WITH MODERATE NE TO E FLOW ACROSS THE CENTRAL AND SW GULF WATERS. MIXED CLOUDINESS PERSISTS ALONG A LINGERING BOUNDARY PERSIST ACROSS THE STRAITS OF FLORIDA...AND KEY WEST WEATHER RADAR IS SHOWING PAINTING A STATIONARY LINE OF SHOWERS EXTENDING FROM NEAR THE MIDDLE KEYS TO NEAR HAVANA. LOOKING AHEAD THROUGH FRIDAY...THE HIGH PRES NORTH OF THE AREA WILL CONTINUE TO MOVE EASTWARD INTO THE WESTERN ATLC OFF THE CAROLINA COAST. SOUTHERLY RETURN FLOW WILL INCREASE OVER THE FAR WESTERN GULF BETWEEN THE EXITING HIGH PRES AND A COLD FRONT MOVING THROUGH TEXAS. CARIBBEAN SEA... HIGH PRES NORTH OF THE AREA IS MAINTAINING FRESH TO STRONG TRADE WIND FLOW ACROSS THE AREA. LOW LEVEL CONVERGENCE OF THESE WINDS IS RESULTING IN BROKEN TO OVERCAST LOW TO MID LEVEL CLOUDINESS ACROSS THE SOUTHERN CARIBBEAN...PARTICULARLY ALONG THE COASTS FROM VENEZUELA TO COLOMBIA AND EASTERN PANAMA. AN EARLIER ALTIMETER PASS INDICATED SEAS OF 8 TO 10 FT IN THE SOUTH CENTRAL CARIBBEAN NOT FAR OFF THE THE COAST OF COLOMBIA IN AN AREA OF 25 TO 30 KT TRADE WIND FLOW WHERE WINDS TO GALE FORCE ARE EXPECTED BY SUNRISE. FRESH E FLOW IS ALSO NOTED BY SHIP OBSERVATIONS ACROSS THE NW CARIBBEAN AS WELL. DEEP LAYER MOISTURE REMAINS LIMITED AS IS TYPICAL THIS TIME OF YEAR IN THE CARIBBEAN...AND OTHER THAN IN THE AREA OF THE TRADE WIND CONVERGENCE IN THE SOUTHERN CARIBBEAN AND WITHIN 120 NM DOWNWIND OF THE LEEWARD AND WINDWARD ISLANDS...NO SIGNIFICANT SHOWER ACTIVITY IS NOTED OR ANTICIPATED. HISPANIOLA... AN UPPER DISTURBANCE PASSED TO THE NE OF THE ISLAND YESTERDAY. NO OTHER FEATURES ARE NOTED IN SATELLITE IMAGERY...WITH UPPER RIDGING IN PLACE THROUGH THE NEXT 48 HOURS. OTHER THAN A FEW AFTERNOON SHOWERS OVER THE HIGHER TERRAIN...FAIR CONDITIONS WILL PERSIST INTO FRIDAY. THE TAIL END OF A WEAK FRONT WILL PASS N OF THE ISLAND LATE FRIDAY INTO SATURDAY...INCREASING THE CHANCE OF SHOWERS SLIGHTLY. ATLANTIC... A COLD FRONT EXTENDS FROM 32N58W TO THE SOUTHERN BAHAMAS...THEN AS A WEAK STATIONARY FRONT TO THE SE GULF OF MEXICO. MULTI-LAYER CLOUDINESS PERSISTS ALONG THE FRONT. ZONAL FLOW ALOFT IS ALLOWING THE FRONT TO SLOW AND WEAKEN. A REINFORCING PUSH WILL ALLOW THE FRONT TO CONTINUE EASTWARD FRIDAY INTO SATURDAY N OF 25N...ALTHOUGH THIS WILL HAVE LITTLE IMPACT AT THE SURFACE. HIGH PRES WILL BUILD OFF THE CAROLINAS THROUGH FRIDAY...MAINTAINING STRONG TRADE WIND FLOW OVER THE TROPICAL ATLC WATERS WEST OF 50W INTO THE WEEKEND. A SHORT WAVE MID TO UPPER FROM 31N50W TO THE LEEWARD ISLANDS CONTINUES TO SHIFT TO THE SOUTHEAST. THERE IS ENOUGH LIFT ON THE SE SIDE OF THIS FEATURE TO SUPPORT AREAS OF SHOWERS WITHIN 180 NM NE OF THE LEEWARD ISLANDS. THESE SHOWERS ARE MOVING EASTWARD AND REACHING AS FAR AS PUERTO RICO. FARTHER EAST...A PERSISTENT UPPER LOW/TROUGH NEAR 27N35W IS FORMING A REX BLOCK PATTERN WITH AN UPPER RIDGE CENTERED NEAR 37N27W. UPPER DIVERGENCE ON THE SE SIDE OF THIS FEATURE WILL CONTINUE TO MAINTAIN UNSETTLED WEATHER N OF 15N BETWEEN 20W AND 35W THROUGH TODAY. THE UPPER TROUGH IS EXPECTED TO WEAKEN AND LIFT NE THROUGH FRI. ASSOCIATED 1027 MB SURFACE HIGH CENTERED NEAR 32N29W WILL MAINTAIN MODERATE TO FRESH TRADE WIND FLOW SOUTH OF 15N THROUGH FRIDAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ CHRISTENSEN