000 AXNT20 KNHC 110508 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI APR 11 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0345 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N8W 4N11W 5N17W THEN ALONG THE EQUATOR BETWEEN 26W-45W TO 1S48W. A WEAK 1010 MB LOW IS ALONG THE ITCZ AXIS NEAR 5N16W MOVING RAPIDLY WESTWARD. THE CONVECTION PREVIOUSLY ASSOCIATED WITH THIS LOW HAS DISSIPATED. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 1N-4N BETWEEN 11W-22W AND WITHIN 120/150 NM OF THE ITCZ AXIS FROM 32W-50W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE EXTENDS OVER THE GULF FROM AN UPPER HIGH ALONG THE NW COAST OF THE YUCATAN PENINSULA NNE TO OVER THE FLORIDA PANHANDLE AND ALONG THE APPALACHIAN MOUNTAINS. A WEAK SURFACE RIDGE EXTENDS OVER FLORIDA AND W ATLC ANCHORED BY A HIGH ALONG THE COAST OF NORTH/SOUTH CAROLINA BORDER. STRONG SUBSIDENCE AND DRY AIR COVERS MOST OF THE GULF WITH SOME OVERRIDING UPPER LEVEL MOISTURE STREAMING ACROSS MEXICO AND ALONG THE COAST OF TEXAS. A LARGE UPPER TROUGH IS OVER THE CENTRAL US WITH A FRONTAL SYSTEM WELL INLAND. STRONG SOUTHERLY SURFACE WINDS DOMINATE ALL BUT THE NE GULF TONIGHT WITH RELATIVELY CLEAR SKIES. A FRONT IS EXPECTED TO ENTER THE GULF OFF THE TEXAS COAST LATE FRI INTO THE NIGHT. CARIBBEAN SEA... UPPER TROUGH EXTENDS FROM THE W ATLC ACROSS THE GREATER ANTILLES INTO THE N CARIBBEAN N OF 16N FROM THE VIRGIN ISLANDS TO CENTRAL CUBA BUT DUE TO THE STRONG SUBSIDENCE AND DRY AIR THERE IS ONLY SCATTERED SHOWERS AND POSSIBLE LINGERING THUNDERSTORMS THAT FORMED THIS AFTERNOON OVER HISPANIOLA AND CUBA MOVING OVER THE CARIBBEAN WATERS WITHIN 90 NM ALONG THE COAST. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE CARIBBEAN ANCHORED OVER SOUTH AMERICA. MODERATE/STRONG E TRADE WINDS WILL CONTINUE ACROSS THE CARIBBEAN WITH THE STRONGEST WINDS REMAINING ALONG THE COAST OF COLOMBIA. THESE TRADE WINDS CONTINUE TO USHER IN SOME LOW LEVEL ISOLATED SHOWERS FROM 12N-16N E OF 70W TO OVER THE WINDWARD ISLANDS. UPPER LEVEL DIVERGENCE IS S OF PANAMA AND COSTA RICA GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS INLAND AND ALONG THE IMMEDIATE COASTAL WATERS. OTHERWISE THE REMAINDER OF THE CARIBBEAN IS RELATIVELY CLEAR AGAIN TONIGHT. ATLANTIC OCEAN... SHORTWAVE UPPER TROUGH COVERS THE W ATLC FROM FLORIDA TO 42W WITH A COMPLEX FRONTAL SYSTEM EXTENDING FROM A 1009 MB LOW NEAR 30N44W ALONG 26N46W TO A 1015 MB LOW NEAR 28N59W ALONG 24N62W TO NEAR 31N74W GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM OF THE FRONTS E OF 63W. WEAK SURFACE RIDGE IS NW OF THE FRONTAL BOUNDARY ANCHORED BY A 1019 MB HIGH ALONG THE COAST OF NORTH/SOUTH CAROLINA BORDER AND A 1022 MB HIGH TO THE E NEAR 24N67W. BROAD LOW AMPLITUDE UPPER RIDGE COVERS THE CENTRAL INTO THE E ATLC THAT ALSO COVERS THE TROPICS. A SURFACE RIDGE COVERS THE E ATLC E OF 40W TO INLAND OVER NW AFRICA ANCHORED BY A 1025 MB HIGH JUST S OF THE AZORES. $$ WALLACE