000 AXNT20 KNHC 250508 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED JUN 25 2008 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0415 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 44W S OF 11N MOVING W NEAR 15 KT. WEAK INVERTED-V CURVATURE IN THE MID LEVELS. THE MIMIC-TPW ANIMATION CONTINUES TO SHOW A SURGE IN MOISTURE IN THE VICINITY OF THIS WAVE SOUTH OF THE ITCZ WITH NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE REMAINS ALONG 74W S OF 21N MOVING W NEAR 15 KT. SATELLITE SIGNATURE IS CURRENTLY OBSCURED BY HIGH CLOUDS. THE MIMIC-TPW ANIMATION CONTINUES TO SHOW A SURGE IN MOISTURE COVERING THE CENTRAL CARIBBEAN. WAVE IS NOW MOVING BENEATH AN UPPER TROUGH AXIS LIMITING DIFFLUENCE ALOFT THUS LIMITING ANY DEEP CONVECTION. ISOLATED SHOWERS ARE POSSIBLE FROM 18N-22N BETWEEN 70W-74W INCLUDING HAITI TO OVER THE TURKS AND CAICOS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 6N29W 5N35W 5N49W TO 6N56W. SCATTERED MODERATE/STRONG CONVECTION COVERS THE AREA FROM 5N-11N BETWEEN 21W AND THE COAST OF W AFRICA AND FROM 5N-8N BETWEEN 49W-52W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 9N-12N W OF 56W INTO THE SE CARIBBEAN INCLUDING TRINIDAD AND TOBAGO. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER TROUGH EXTENDS FROM AN UPPER LOW IN THE NW ATLC ACROSS THE CAROLINAS AND THE SE US TO OVER THE W HALF OF THE GULF TO S MEXICO AND THE W BAY OF CAMPECHE. AN UPPER LEVEL RIDGE EXTENDS FROM THE CARIBBEAN OVER THE REMAINDER OF THE GULF INTO THE W ATLC ACROSS THE N BAHAMA ISLANDS. THIS CONTINUES TO SUPPLY THE E GULF WITH ABUNDANCE OF TROPICAL MOISTURE AS WELL AS DIFFLUENCE ALOFT. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE E GULF SW OF A LINE FROM N OF TAMPA FLORIDA TO THE W BAY OF CAMPECHE WITH THE HEAVIEST ACTIVITY IN THE FLORIDA STRAITS. SURFACE RIDGE REMAINS WEAK BUT DUE TO THE LOWERING PRESSURE OVER THE CENTRAL US WINDS WILL BE INCREASING OVERNIGHT ACROSS THE GULF. CARIBBEAN... AN UPPER RIDGE ANCHORED IN THE E PACIFIC REGION EXTENDS ACROSS HONDURAS/NICARAGUA ACROSS CENTRAL CUBA INTO THE W ATLC COVERING THE AREA W OF 80W WHILE A SECOND UPPER RIDGE ANCHORED E OF THE WINDWARD ISLANDS COVERS THE E CARIBBEAN. A WEAKENING UPPER TROUGH IS BETWEEN THESE UPPER RIDGES EXTENDING FROM THE W ATLC INTO THE CARIBBEAN NEAR THE E CUBA/WINDWARD PASSAGE SW TO 12N78W. UPPER LEVEL DIFFLUENCE CONTINUES TO GENERATE SCATTERED SHOWERS/THUNDERSTORMS OVER THE NW CARIBBEAN NW OF A LINE FROM CUBA NEAR 20N77W TO NICARAGUA NEAR 14N84W WITH THE FROM 11N-15N W OF 80W TO INLAND OVER HEAVIEST ACTIVITY N OF 20N ACROSS CUBA BETWEEN 78W-83W. THE ITCZ CROSSES PANAMA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE AREA S OF 11N TO INLAND OVER COLOMBIA AND PANAMA BETWEEN 73W-82W. UPPER LEVEL MOISTURE IS BEING DRAWN ACROSS THE E CARIBBEAN ENHANCING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF A LINE FROM 14N70W INTO THE TROPICAL ATLC NEAR 12N60W. MODERATE/STRONG EASTERLY TRADE WINDS CONTINUE TO DOMINATE MOST OF THE CARIBBEAN DUE TO THE TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE OVER THE ATLC AND LOWER PRESSURE OVER SOUTH AMERICA. ATLANTIC... AN UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS CENTRAL CUBA OVER THE N BAHAMA ISLANDS TO NEAR 30N74W PROVIDING UPPER DIFFLUENCE AND CONTINUING TO GENERATE CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 28N W OF 73W TO OVER CUBA AND INTO THE FLORIDA STRAITS. A BROADER UPPER RIDGE DOMINATES THE CENTRAL ATLC ANCHORED BY AN UPPER HIGH NEAR 32N49W. THE UPPER TROUGH THAT HAS TRANSVERSED THE ATLC BASIN OVER THE PAST FEW DAYS IS BEGINNING TO BREAK DOWN WITH AN UPPER TROUGH OVER THE W ATLC EXTENDING FROM 28N63W INTO THE CARIBBEAN NEAR E CUBA/WINDWARD PASSAGE WHILE AN UPPER TROUGH DIGS S OVER THE E ATLC EXTENDING THROUGH 32N32W TO 21N35W. THE UPPER RIDGE THAT DOMINATED THE TROPICS OVER THE PAST FEW DAYS IS ALSO BEGINNING TO BREAK DOWN WITH AND UPPER HIGH E OF THE WINDWARD ISLANDS NEAR 12N55W COVERING THE AREA E OF 46W INTO THE CARIBBEAN AND A SECOND UPPER HIGH OFF THE COAST OF AFRICA NEAR 14N18W COVERING THE E TROPICS E OF 30W. THE SURFACE RIDGE REMAINS IN CONTROL OF THE ATLC BASIN FROM AFRICA INTO THE GULF OF MEXICO ANCHORED BY A 1029 MB HIGH CENTERED NEAR 32N54W. MODERATE SUBSIDENCE AND A FAIR AMOUNT OF DRY STABLE AIR ALSO DOMINATES THE ATLC E OF 60W GIVING THE AREA FAIR WEATHER AGAIN TONIGHT. THE LAST VISIBLE SATELLITE IMAGES CONTINUE TO SHOW A WIDE SWATH OF AFRICAN DUST TRANSVERSING THE ATLC S OF 22N FROM AFRICA TO THE CARIBBEAN AND A NARROWER SWATH EXTENDING N OF THE CARIBBEAN OVER THE W ATLC FROM 20N-30N BETWEEN 60W-70W. $$ WALLACE