000 AXNT20 KNHC 031735 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN MAY 03 2009 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...THE ITCZ... THE ITCZ AXIS EXTENDS FROM OFF THE COAST OF W AFRICA NEAR 06N03E TO 01N02W TO THE EQUATOR AT 15W TO NE BRAZIL NEAR 01S45W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OCCURRING NEAR THE COAST OF AFRICA N OF THE EQUATOR AND E OF 07W AND NEAR THE COAST OF BRAZIL FROM THE EQUATOR TO 07S W OF 30W. ...DISCUSSION... GULF OF MEXICO... THE COMBINATION OF A BROAD AREA OF LOW PRESSURE ALONG THE LOWER TEXAS/MEXICAN COAST AND THE SURFACE RIDGE PUSHING UP AGAINST FLORIDA IS PRODUCING SE WINDS FROM 15 TO 25 KT...WITH THE HIGHER WINDS IN THE CENTRAL AND WESTERN GULF. NO ORGANIZED AREAS OF DEEP CONVECTION ARE OCCURRING OVER THE GULF...THOUGH SEVERE WEATHER IS RACING ACROSS LOUISIANA AND MISSISSIPPI CURRENTLY JUST A FEW DOZEN MILES INLAND. UPPER LEVEL WINDS AND THE WATER VAPOR IMAGERY INDICATE RIDGING AND SUBSIDENT FLOW OVER THE GULF. A BAND OF CIRRUS STRETCHES FROM THE WESTERN TO THE NORTHEASTERN GULF ON THE NORTH SIDE OF THE UPPER RIDGE LINE. THE WEAK FRONTAL BOUNDARY CURRENTLY OVER SOUTHERN TEXAS MAY MAKE A BRIEF APPEARANCE OVER THE EXTREME NORTHWESTERN GULF...BUT WOULD SOON BE REPLACED BY SOUTHEASTERLY RETURN FLOW. THE SOUTHEASTERLY WINDS OVER THE GULF MAY WEAKEN SLIGHTLY OVER THE NEXT TWO DAYS AS THE BROAD LOW WEAKENS AND THE RIDGE RETREATS. CARIBBEAN SEA... THE TRADEWINDS HAVE SLACKENED SOMEWHAT COMPARED WITH YESTERDAY WITH WINDS 20 KT OR LESS THROUGHOUT THE CARIBBEAN AS THE RIDGING TO THE NORTH OF THE CARIBBEAN HAS WEAKENED. A SURFACE TROUGH EXISTS ALONG THE LESSER ANTILLES...WHICH APPARENTLY BROKE OFF FROM THE PARENT TROUGH WHICH HAS CONTINUED PROGRESSING NORTHEASTWARD TODAY. SCATTERED SHOWERS ARE AFFECTING THE LESSER ANTILLES AND INTO THE ATLANTIC FOR ABOUT 180 NM E OF THE TROUGH AXIS...AS OBSERVED FROM VISIBLE SATELLITE IMAGERY AND GUADELOUPE /MARTINIQUE RADARS. THERE IS SCATTERED MODERATE CONVECTION WITHIN 120 NM OF THE EASTERN PANAMA AND WESTERN COLUMBIA COAST AS WELL AS OVER HISPANIOLA AND JUST TO THE SOUTHWEST OF THE ISLAND. ELSEWHERE NO ORGANIZED DEEP CONVECTION IS OBSERVED. IN THE UPPER LEVELS...WINDS UP TO 70 KT ARE ANTICYCLONICALLY TURNING NORTH OF A RIDGE CENTERED NEAR 10N71W. CIRRUS IS BEING ADVECTED EASTWARD BY THESE WINDS FROM OUTFLOW PRODUCED BY DEEP CONVECTION OVER THE SOUTHWESTERN CARIBBEAN...CENTRAL AMERICA...AND THE NORTHEAST PACIFIC'S ITCZ. MOST OF THE CARIBBEAN SHOULD REMAIN TRANQUIL DURING THE NEXT TWO DAYS...EXCEPT FOR THE NORTHEASTERN CARIBBEAN ISLANDS WHICH MAY SEE SOME ENHANCED SHOWERS AND DEEP CONVECTION DUE TO THE TROUGH AS IT MOVES NORTHWESTWARD. ATLANTIC OCEAN... THE ATLANTIC IS DOMINATED BY A SURFACE HIGH PRESSURE CENTERED WAY UP AT 47N23W WITH RIDGING EXTENDING WEST-SOUTHWESTWARD TO 32N60W AND TO THE FLORIDA PENINSULA. TWO SMALLER SCALE FEATURES ARE OF INTEREST. THE FIRST IS A SURFACE TROUGH NORTH OF PUERTO RICO ALONG 65W FROM ROUGHLY 21N TO 28N. THIS TROUGH HAS BEEN PROGRESSING NORTHWESTWARD AND A PIECE MAY HAVE BROKEN OFF AND IS NEAR THE LESSER ANTILLES...AS DESCRIBED ABOVE. A MID TO UPPER LOW EXISTS WEST OF THE SURFACE TROUGH AND IS HELPING TO ADVECT MID LEVEL CLOUDINESS OVER THE TROUGH AND TO ITS EAST. SCATTERED SHOWERS ARE PRESENT WITHIN 60 NM W OF THE TROUGH AXIS AND 180 NM E OF THE AXIS. THE SURFACE WINDS ARE ENHANCED E OF THE TROUGH AXIS WITH EAST TO SOUTHEAST WINDS 20 TO 25 KT. THE SECOND FEATURE IS A TROUGH...AN OLD FRONTAL BOUNDARY...EXTENDING FROM 25N42W TO 32N38W TO 43N35W. SCATTERED SHOWERS ARE OCCURRING WITHIN 180 NM E OF THE TROUGH AXIS N OF 27N. A BOARD UPPER LOW CENTERED NEAR 31N40W ASSOCIATED WITH THE SURFACE TROUGH DOMINATES THE UPPER WINDS OVER MOST OF THE REGION WITH CYCLONICALLY TURNING WINDS OBSERVED ALL THE WAY DOWN TO 10N. FINALLY...THERE IS AN ENHANCEMENT OF NORTHEASTERLY SURFACE WINDS OF 20-25 KT NORTHEAST OF THE CAPE VERDE ISLANDS TO THE WEST COAST OF MAURITANIA AND WESTERN SAHARA. OVER THE NEXT TWO DAYS...THE SURFACE TROUGH NORTH OF PUERTO RICO SHOULD CONTINUE MOVING NORTHWESTWARD...WHILE THE TROUGH IN THE CENTRAL ATLANTIC SHOULD GRADUALLY FILL. $$ LANDSEA