000 AXNT20 KNHC 051705 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE MAY 05 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 1645 UTC. ...THE ITCZ... THE ITCZ AXIS IS ALONG 7N8W 4N12W 2N19W CROSSING THE EQUATOR NEAR 30W AND CONTINUING JUST S OF THE EQUATOR TO 1S50W. SCATTERED/NUMEROUS STRONG CONVECTION IS MOVING W FROM THE FAR W COAST OF AFRICA ACROSS THE PRIME MERIDIAN TO 3W ENCOMPASSING THE SW COAST OF AFRICA TO JUST S OF THE EQUATOR. A SMALLER AREA OF SIMILAR CONVECTION IS N OF THE ITCZ WITHIN 75 NM OF LINE FROM 7N14W TO 4N21W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 4N TO S OF THE EQUATOR BETWEEN 6W-24W AND S OF 2N TO INLAND OVER SOUTH AMERICA BETWEEN 41W-49W. ...DISCUSSION... GULF OF MEXICO... BROAD DEEP LAYERED TROUGH REMAINS OVER THE E U.S. DIPPING S OVER THE FLORIDA PENINSULA WITH THE ASSOCIATED FRONTAL BOUNDARY INLAND ACROSS THE GULF COAST STATES INTO TEXAS. VERY LITTLE IN THE WAY OF PRECIPITATION IS FOUND S OF THE FRONT AS LIGHT SE SURFACE FLOW IS EVIDENT FROM SHIP AND BUOY OBSERVATIONS ACROSS THE GULF. THESE WINDS ARE LOCATED ON THE W PERIPHERY OF A SURFACE RIDGE THAT EXTENDS FROM THE W ATLC ACROSS THE FLORIDA PENINSULA TO OVER THE E GULF. OTHERWISE...FAIR WEATHER CONDITIONS CONTINUE ACROSS THE GULF TODAY WITH ONLY DEBRIS MOISTURE IN THE FORM OF HIGH CLOUDS STREAMING ACROSS THE CENTRAL GULF. CARIBBEAN SEA... A BROAD UPPER RIDGE DOMINATES THE W CARIBBEAN ANCHORED OVER COSTA RICA WHICH IS ADVECTING TROPICAL MOISTURE OVER THE YUCATAN AND INTO THE GULF OF HONDURAS TO 75W. THIS MOISTURE IS RESULTANT DEBRIS CLOUDINESS FROM SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER CENTRAL AMERICA. A SURFACE TROUGH EXTENDS OVER THE E CARIBBEAN FROM 20N66W ACROSS PUERTO RICO TO NEAR 13N65W. THIS SURFACE TROUGH CONTINUES TO PRODUCE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER THE FAR E CARIBBEAN AND LESSER ANTILLES E OF THE AXIS. LIGHT TO MODERATE TRADE WINDS COVER THE CARIBBEAN PRIMARILY DUE TO A RELAXED PRESSURE GRADIENT LEAVING THE REMAINDER OF THE CARIBBEAN WITH SOME ISOLATED LOW LEVEL SHOWERS MOVING WESTWARD IN CONVERGENT SURFACE FLOW ACROSS THE BASIN S OF 16N. ATLANTIC OCEAN... THE ATLANTIC BASIN IS DOMINATED BY SURFACE HIGH PRESSURE RIDGE ANCHORED NORTH OF THE DISCUSSION AREA. ONE WEAKNESS IN THIS SURFACE RIDGE IS LOCATED ACROSS THE W ATLC AS AN UPPER LEVEL LOW CENTERED NEAR 25N69W IS PROVIDING SUPPORT FOR A SURFACE TROUGH THAT EXTENDS TO JUST N OF THE TURKS AND CAICOS NEAR 23N72W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OBSERVED E OF THE SURFACE TROUGH WITHIN 90 NM OF A LINE FROM 23N66W TO 28N69W. THIS ACTIVITY IS LOCATED UNDER A LARGE MID/UPPER LEVEL DIFFLUENT ZONE ACROSS THE W ATLC DRAWING TROPICAL MOISTURE FROM THE CARIBBEAN N INTO THE UPPER LOW. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS EXTEND FARTHER TO THE SE ACROSS THE LESSER ANTILLES AND TROPICAL ATLC FROM 13N-21N BETWEEN 53W-66W. THE SECOND WEAKNESS IN THE ATLC SURFACE RIDGE EXTENDS OVER THE E/CENTRAL ATLC AS A SECOND LARGER UPPER LEVEL LOW SPINS NEAR 29N42W PROVIDING SUPPORT FOR A SURFACE TROUGH THAT EXTENDS THROUGH 32N36W ALONG 28N40W TO 23N43W GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS FROM 28N TO BEYOND 32N BETWEEN 33W-43W. $$ WALLACE