000 AXNT20 KNHC 231011 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EST WED APR 23 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 1115 UTC. ...THE ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL BORDER SECTIONS OF GUINEA-BISSAU AND GUINEA NEAR 11N15W TO 03N24W. THE ITCZ EXTENDS FROM THAT POINT TO THE COAST OF BRAZIL NEAR 00N50W. A SURFACE TROUGH IS ALONG 06N11W TO 03N24W. SCATTERED STRONG CONVECTION WAS NOTED WITHIN 120 NM NORTH OF THE SURFACE TROUGH. ...DISCUSSION... ...THE GULF OF MEXICO... A 1016 MB SURFACE HIGH IS CENTERED OVER THE WEST CENTRAL GULF OF MEXICO NEAR 27N93W. AS THERE IS ALMOST NO PRESSURE GRADIENT PRESENT...WINDS THROUGHOUT THE GULF ARE GENTLE BREEZE CONDITIONS OR WEAKER. NO DEEP CONVECTION NOR ANY WIDESPREAD SHOWERS HAVE BEEN PRESENT ACROSS THE GULF THIS EVENING. HOWEVER...SCATTERED MODERATE CONVECTION THAT BROKE OUT MAINLY OVER THE EAST-FACING SLOPES OF THE SIERRA MADRE MOUNTAINS OF MEXICO HAS DISSIPATED. THE WEAK SURFACE HIGH WILL DRIFT EASTWARD DURING THE NEXT TWO DAYS...THOUGH WINDS OVER THE GULF WILL REMAIN LIGHT. THE DIURNALLY FLUCTUATING CONVECTION OVER MEXICO WILL CONTINUE...BUT THERE IS LITTLE CHANCE OF DEEP CONVECTION OVER THE GULF DURING THE NEXT COUPLE OF DAYS. ...THE CARIBBEAN SEA... A SURFACE TROUGH...THE REMNANTS OF A COLD FRONT...EXTEND FROM HISPANIOLA WEST-SOUTHWESTWARD TO JUST NORTH OF JAMAICA TO THE NORTHWESTERN CARIBBEAN SEA. THIS HAS HELPED INITIATE ISOLATED MODERATE CONVECTION OVER PORTIONS OF CUBA...JAMAICA...AND THE DOMINICAN REPUBLIC LATE ON TUESDAY...BUT HAS NOW SINCE DISSIPATED. SCATTERED SHOWERS EXIST WITHIN ABOUT 60 NM OF THE TROUGH. THE TROUGH SHOULD CONTINUE TO PROVIDE SOME MOISTURE AND FORCING FOR ISOLATED DEEP CONVECTION OVER EASTERN CUBA...EASTERN BAHAMAS...HISPANIOLA DURING THE NEXT TWO DAYS. IN ADDITION... SCATTERED MODERATE CONVECTION ALSO OCCURRED DURING THE LAST SEVERAL HOURS OVER NEAR THE COASTS OF COSTA RICA...PANAMA...AND COLOMBIA...DUE TO LAND BREEZES INTERACTING WITH SUBSTANTIAL AMOUNTS OF MOISTURE. DEEP CONVECTION OVER PORTIONS OF CENTRAL AMERICA AND NORTHERNMOST SOUTH AMERICA DURING AFTERNOONS AND EARLY EVENING DURING THE NEXT COUPLE OF DAYS SHOULD CONTINUE. THE WEAK NORTH-SOUTH PRESSURE GRADIENT ACROSS THE CARIBBEAN IS PRODUCING ONLY GENTLE TO MODERATE BREEZE TRADEWINDS. OVER THE NEXT COUPLE DAYS...THE TRADEWINDS WILL REBOUND TO SLIGHTLY BREEZIER CONDITIONS. ...HISPANIOLA... A SURFACE TROUGH...THE REMNANTS OF A COLD FRONT...EXTEND FROM HISPANIOLA WEST-SOUTHWESTWARD TO JUST NORTH OF JAMAICA. THIS HAS HELPED INITIATE ISOLATED MODERATE CONVECTION OVER PORTIONS OF THE DOMINICAN REPUBLIC LATE ON TUESDAY. SCATTERED SHOWERS ALSO EXIST WITHIN ABOUT 60 NM OF THE TROUGH. THE TROUGH SHOULD CONTINUE TO PROVIDE SOME MOISTURE AND FORCING FOR ISOLATED DEEP CONVECTION OVER HISPANIOLA DURING THE NEXT TWO DAYS. ...THE ATLANTIC OCEAN... A TROUGH EXTENDS SOUTH-SOUTHWESTWARD FROM AN OCCLUDING GALE- FORCE LOW OF 993 MB PRESSURE CENTERED AT 40N59W...SEVERAL HUNDRED MILES NORTHEAST OF BERMUDA. THE TROUGH ENTERS OUR AREA AT 32N57W AND EXTENDS TO HISPANIOLA. SCATTERED SHOWERS AND ISOLATED MODERATE CONVECTION ARE PRESENT WITHIN 60 NM OF THE TROUGH. A LARGE SWATH OF FRESH TO STRONG BREEZE SOUTHERLIES AHEAD OF THE TROUGH WILL CONTINUE TO ADVECT MOIST AIR POLEWARD DURING THE NEXT COUPLE OF DAYS AND PROMOTE SHOWERS AND THUNDERSTORMS. A NEW COLD FRONT IS EMERGING OFF OF THE U.S. ATLANTIC COAST CURRENTLY AND WILL QUICKLY PUSH EASTWARD AND MERGE IN A COUPLE OF DAYS WITH THE TROUGH. WINDS ON BOTH SIDES OF THIS NEW FRONT MAY REACH STRONG BREEZE CONDITIONS IN OUR AREA OF RESPONSIBILITY. FARTHER EAST...A FRONTAL BOUNDARY IS JUST WITHIN OUR NORTHERN BOUNDARY. THE FEATURE IS A STATIONARY FRONT FROM 31N41W TO 28N33W...THEN TRANSITIONS TO A COLD FRONT TO 32N18W. SCATTERED SHOWERS EXIST WITHIN 120 NM OF THE FRONT...THOUGH WINDS ARE WEAK ON BOTH SIDES OF THE FRONT. THE FRONTAL FEATURE SHOULD GRADUALLY FADE WITHIN THE NEXT DAY OR TWO. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LANDSEA