000 AXNT20 KNHC 010010 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAR 31 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N5W 1N20W CROSSING THE EQUATOR NEAR 24W TO 2S45W. SCATTERED STRONG CONVECTION IS WITHIN 90-120 NM OF THE AXIS E OF 11W TO THE COAST OF LIBERIA AND COTE D'IVOIRE. SCATTERED MODERATE TO STRONG IS FROM THE EQUATOR TO 3S BETWEEN 24W AND 30W. SCATTERED MODERATE ISOLATED STRONG ELSEWHERE FROM THE EQUATOR TO 3N BETWEEN 20W-36W. SCATTERED MODERATE N OF THE AXIS TO 2N W OF 36W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED IN THE E PACIFIC ALONG 101W/102W IS EXERTING AN INFLUENCE OVER MOST OF THE GULF WITH ASSOCIATED ANTICYCLONIC FLOW. SHARP MID TO UPPER LEVEL TROUGH MOVING ACROSS THE GREAT PLAINS IS IMPINGING UPON THE RIDGE OVER THE FAR NW GULF. UPPER LEVEL MOISTURE IS STREAMING EWD ACROSS THE NW GULF IN ADVANCE OF THE UPPER TROUGH IN AN AREA OF SOMEWHAT DIFFLUENT FLOW. MODERATE TO STRONG UPPER LEVEL SUBSIDENCE COVERS THE REMAINDER OF THE GULF. AT THE SURFACE...A WEAKENING STATIONARY FRONT EXTENDS FROM THE W COAST OF FLORIDA JUST S OF TAMPA TO NEAR BILOXI MISSISSIPPI. A PATCH OF STRATUS CLOUDS WAS NOTED N OF THE FRONTAL BOUNDARY OFF THE COAST OF THE FL PANHANDLE BUT WAS GRADUALLY DISSIPATING IN THE FACE OF INCREASING SE FLOW. THIS FLOW WAS ALSO ADVECTING STREAMERS OF LOW CLOUDS ELSEWHERE OVER THE GULF E OF 90W AND THE FAR W GULF MAINLY W OF 94W. CARIBBEAN SEA... A SHARPENING UPPER TROUGH WAS THE DOMINANT FEATURE OVER THE CARIBBEAN SEA AND EXTENDED FROM JUST E OF THE CENTRAL BAHAMAS SW TO A BASE NEAR 14N81W. THERE ARE INDICATIONS THAT A CLOSED UPPER LOW MAY BE IN THE PROCESS OF DEVELOPING WITHIN THIS TROUGH IN THE VICINITY OF E CUBA AND THE ADJACENT WATERS. NW UPPER LEVEL FLOW WAS INDICATED W OF THE TROUGH AXIS AND BROAD WSW FLOW E OF THE AXIS WITH STRONG SUBSIDENCE NOTED OVER THE ENTIRE CARIBBEAN EXCEPT N OF 17N AND E OF THE UPPER TROUGH AXIS ...GENERALLY OVER E CUBA AND HISPANIOLA. AT THE SURFACE... A TROUGH...POSSIBLY AN EARLY SEASON TROPICAL WAVE HAS JUST CROSSED THE LESSER ANTILLES AND EXTENDS FROM 11 TO 20N ALONG 62W. SCATTERED LOW TOP SHOWERS ARE ACCOMPANYING THE TROUGH OVER MOST OF THE WINDWARD ISLANDS WITH A NOTICEABLE WIND SHIFT OCCURRING BETWEEN ST MAARTEN AND ANTIGUA. ELSEWHERE OVER THE CARIBBEAN...MODERATE EASTERLY TRADE WINDS DOMINATE WITH LOW TOP SHOWERS. THE EXCEPTION IS THE AREA DOMINATED BY THE UPPER TROUGH WHERE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS CONTINUE TO BE GENERATED N OF 16N TO OVER HISPANIOLA AND E CUBA BETWEEN 71W-79W INCLUDING JAMAICA. ATLANTIC OCEAN... UPPER TROUGH LEVEL TROUGH EXTENDS ACROSS THE W ATLC FROM NEAR 32N54W SWWD ACROSS 28N60W TO JUST E OF THE CENTRAL BAHAMAS AND CONNECTS WITH THE UPPER TROUGH NOTED IN THE CARIBBEAN SECTION. THIS TROUGH TRIGGERED SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE E-CENTRAL BAHAMAS EXTENDING SWD TO HISPANIOLA. ASSOCIATED COLD FRONT ENTERING THE REGION NEAR 32N46W EXTENDING TO 25N60W WHERE IT BECOMES A WEAKENING FRONT TO 26N70W. A WARM FRONT OVER THE FAR NW PORTION OF THE AREA FROM 32N81W TO THE FL COAST NEAR ST AUGUSTINE WAS MOVING INLAND. ELSEWHERE BROAD ZONAL FLOW PREVAILS OVER THE ATLC N OF 20N AND E OF 50W. THE FLOW TURNS MORE ANTICYCLONIC OVER THE TROPICAL ATLC S OF 20N. MODERATE SUBSIDENCE PREVAILS OVER THE REGION. AT THE SURFACE...BROAD SURFACE RIDGE COVERS THE ATLC W OF 50W AND ANOTHER RIDGE DOMINATED THE AREA N OF 14N E OF 40W. A WEAKNESS WAS NOTED IN THE IMMEDIATE VICINITY OF THE CENTRAL ATLC COLD FRONT. $$ COBB