000 AXNT20 KNHC 291750 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU MAY 29 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 29W/30W S OF 15N MOVING W NEAR 15 KT. WELL DEFINED INVERTED-V CURVATURE AHEAD OF A SURGE COMING OFF THE COAST OF AFRICA. SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 5N-8N 28W-31W. TROPICAL WAVE IS ALONG 43W S OF 8N MOVING W 10-15 KT. WEAK LOW AMPLITUDE INVERTED-V CURVATURE EVIDENT ON SATELLITE IMAGERY WITH ONLY ISOLATED MODERATE CONVECTION FROM 4N-5N BETWEEN 41W-45W. TROPICAL WAVE IS ALONG 71W S OF 21N MOVING W 15-20 KT. WAVE SIGNATURE IS OBSCURED BY HIGH CLOUDS THAT COVER MUCH OF THE CARIBBEAN...HOWEVER GFS MODEL GUIDANCE SUGGESTS SLIGHT LOW-LEVEL CYCLONIC TURNING WHICH IS AIDING IN PRODUCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS PUERTO RICO AND HISPANIOLA. TROPICAL WAVE IS ANALYZED ALONG 84W/85W BETWEEN 12N-20N MOVING NW 10-15 KT. WAVE REMAINS EMBEDDED WITHIN A BROAD AREA OF LOWER PRESSURE AND CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ACROSS THE W CARIBBEAN SEA. THIS WAVE IS MOVING OVER CENTRAL AMERICA AND BEING FORCED NW BY TROPICAL STORM ALMA OFF THE W COAST OF NICARAGUA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N11W 5N17W 3N28W 2N41W 2N45W AND INTO NE BRAZIL NEAR 1N51W. SCATTERED/NUMEROUS STRONG CONVECTION IS WITHIN 90 NM N OF THE AXIS BETWEEN 11W-15W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 200 NM ON EITHER SIDE OF THE AXIS BETWEEN 18W-25W. SCATTERED MODERATE CONVECTION IS FROM 1N-4N BETWEEN 26W-29W. SIMILAR CONVECTION IS WITHIN 60 NM OF A LINE FROM 5N33W TO 4N38W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER LEVEL RIDGE COVERS MEXICO INTO THE GULF W OF 91W ANCHORED OVER N CENTRAL MEXICO. A NARROW INVERTED UPPER TROUGH EXTENDS FROM THE CENTRAL BAY OF CAMPECHE TO THE FLORIDA PANHANDLE NEAR TALLAHASSEE. THE GULF IS UNDER THE CONTROL OF MODERATE/STRONG SUBSIDENCE AND DRY UPPER AIR NW OF A LINE FROM FORT MYERS FLORIDA INTO THE BAY OF CAMPECHE NEAR 21N96W. UPPER LEVEL DIFFLUENCE TO THE SE OF THE UPPER LEVEL TROUGH IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 25N-27N BETWEEN 84W-87W AND S OF 22N INTO THE BAY OF CAMPECHE BETWEEN 92W-95W. WEAK SURFACE RIDGE EXTENDS ACROSS THE N GULF FROM THE W ATLC TO THE TEXAS/MEXICO BORDER WITH MODERATE EASTERLY SURFACE WINDS. THESE WINDS ARE EXPECTED TO PERSIST DURING THE NEXT 24 HOURS. OTHERWISE THE REMAINDER OF THE GULF IS EXPERIENCING RATHER CLEAR SKIES AND FAIR WEATHER. CARIBBEAN SEA... THE CARIBBEAN REMAINS ACTIVE DUE TO THE PRESENCE OF TWO TROPICAL WAVES AS WELL AS A TROPICAL SYSTEM IN THE E PACIFIC OFF THE W COAST OF NICARAGUA. BROAD UPPER RIDGE DOMINATES THE CARIBBEAN WITH THE UPPER HIGH LOCATED OVER TROPICAL STORM ALMA IN THE E PACIFIC. THIS SYSTEM IS ALSO GENERATING A BROAD AREA OF LOWER SURFACE PRESSURE OVER THE W CARIBBEAN. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 14N-19N BETWEEN 74W-80W. SIMILAR CONVECTION IS DEVELOPING WITHIN 120 NM E OF THE TROPICAL WAVE ALONG 85W TO THE COAST OF NICARAGUA. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ALSO COVER THE N CARIBBEAN SEA ALONG THE GREATER ANTILLES N OF 16N. TROPICAL STORM ALMA IN THE E PACIFIC IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 10 TO 15 INCHES OVER PORTIONS OF CENTRAL AMERICA FROM COSTA RICA NW THROUGH PORTIONS OF NICARAGUA...HONDURAS...EL SALVADOR...AND GUATEMALA. ISOLATED MAXIMUM STORM TOTAL AMOUNTS OF 20 INCHES ARE POSSIBLE IN AREAS OF HIGHER TERRAIN. THESE RAINS MAY PRODUCE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES. ATLANTIC OCEAN... AN UPPER RIDGE IS OVER THE W ATLC W OF 66W WITH AN UPPER TROUGH EXTENDING THROUGH 32N55W TO 21N59W. A REMNANT SURFACE TROUGH EXTENDS FROM 31N61W ALONG 27N69W TO THE BAHAMAS NEAR ABACO ISLAND. THIS SURFACE TROUGH IS EMBEDDED WITHIN MODERATE/STRONG SUBSIDENCE AND DRY AIR...THUS NO CONVECTION WITH ONLY ISOLATED SHOWERS WITHIN 120 NM E OF THE N BAHAMAS. SCATTERED SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS ARE FROM CENTRAL CUBA TO PUERTO RICO BETWEEN 64W-79W INCLUDING THE TURKS AND CAICOS. AN UPPER RIDGE EXTENDS FROM THE BROADER UPPER RIDGE OVER THE CARIBBEAN ACROSS THE LEEWARD ISLANDS NE TO BEYOND 32N46W. A SECOND SURFACE TROUGH IS ALONG THE W EDGE OF THE UPPER RIDGE EXTENDING FROM 31N58W ALONG 26N61W TO 23N66W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 150 NM E OF THE TROUGH AXIS N OF 28N AND FROM 21N-25N. BROAD UPPER TROUGH EXTENDS FROM THE E ATLC NEAR 32N28W SW ALONG 25N40W INTO THE TROPICAL ATLC TO NEAR 12N53W. THE E AND CENTRAL ATLC ARE DOMINATED BY A SURFACE RIDGE N OF 20N W OF 53W ANCHORED BY A 1027 MB HIGH NEAR 32N39W. MOSTLY CLEAR SKIES AND FAIR WEATHER ARE EXPECTED TO CONTINUE FOR THE E ATLC. $$ HUFFMAN