000 AXNT20 KNHC 110542 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN MAY 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 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 45W/46W S OF 9N MOVING W 10-15 KT. THE SSMI PRECIPITABLE WATER AND THE LATEST QUIKSCAT PASS CLEARLY SHOWS THE WAVE. SCATTERED MODERATE/STRONG CONVECTION IS FROM 3N-6N BETWEEN 43W-46W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 5N21W 3N33W 4N44W THEN INLAND OVER NE BRAZIL NEAR 1N52W. SCATTERED MODERATE/STRONG CONVECTION IS ON BOTH SIDES OF THE TROPICAL WAVE WITHIN 125 NM N OF THE ITCZ AXIS FROM 40W-51W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION IS FROM 7N TO S OF THE EQUATOR BETWEEN 14W-35W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE COVERS THE GULF ANCHORED OVER THE BAY OF CAMPECHE AND EXTENDS FROM ACROSS MEXICO INTO THE W ATLC. THIS IS DRAWING UPPER LEVEL MOISTURE ACROSS MEXICO TO THE W GULF BUT ONLY IN THE FORM OF HIGH CLOUDS. MODERATE SOUTHERLY FLOW OVER THE GULF IS CURRENTLY BANKING SOME LOW CLOUDS ALONG THE N GULF COAST WITH NO SHOWER ACTIVITY. HOWEVER...THIS SCENARIO WILL CHANGE AS A FRONT MOVES OFF THE TEXAS COAST WITH THE WINDS SHIFTING AROUND TO THE N AND BRINGING SHOWERS AND THUNDERSTORMS TO THE NW GULF LATER THIS MORNING. THIS FRONT WILL CROSS THE GULF AND EXIT ON TUE. CURRENTLY THE SEVERE WEATHER IS OVER ARKANSAS AND N MISSISSIPPI MOVING INTO N ALABAMA. CARIBBEAN SEA... BROAD UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE NW CARIBBEAN N OF 15N W OF 72W. THE UPPER TROUGH IN THE W/CENTRAL ATLC DIPS INTO THE FAR NE CARIBBEAN FROM HISPANIOLA TO THE LEEWARD ISLANDS AND CREATING A SHEAR AXIS THAT EXTENDS FROM THE UPPER TROUGH W TO OVER NICARAGUA. MODERATE TO STRONG EASTERLY TRADE WINDS DOMINATE THE AREA WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. STRONG SURFACE WINDS IS PRODUCING LOW LEVEL CONVERGENCE OVER THE SW CARIBBEAN AND COUPLED WITH LIGHT UPPER LEVEL WINDS ARE GENERATING AN AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 12N TO INLAND OVER PANAMA BETWEEN 77W-82W. OTHERWISE THE CARIBBEAN REMAINS CLEAR TONIGHT. ATLANTIC OCEAN... UPPER RIDGE THAT COVERS THE GULF OF MEXICO EXTENDS OVER THE FAR W ATLC TO NEAR 75W. AN UPPER TROUGH COVERS THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC BETWEEN 60W-75W AND A SHORTWAVE THAT EXTENDS ALONG 63W TO PUERTO RICO. AN UPPER TROUGH COVERS THE E ATLC E OF 35W WITH AN NARROW UPPER RIDGE BETWEEN THESE TWO UPPER TROUGHS. THE UPPER RIDGE IS PRODUCING ENOUGH UPPER LEVEL DIFFLUENCE TO GENERATE AN AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 75 NM OF LINE FROM 26N64W TO 28N53W. THE SURFACE IS DOMINATED BY A RIDGE THAT ENCOMPASSES THE ENTIRE ATLC BASIN E OF 80W ANCHORED BY A WEAK 1021 MB HIGH NEAR 29N43W AND FAIR WEATHER CLOUDS. $$ WALLACE