000 AXNT20 KNHC 160537 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN MAY 16 2010 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 0515 UTC... ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 23W/24W S OF 10N MOVING W NEAR 15 KT. WAVE REMAINS EMBEDDED WITHIN A BROAD MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION DOT THE AREA FROM 3N-8N BETWEEN 19W-26W. TROPICAL WAVE IS ALONG 51W/52W S OF 10N MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN A MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE FROM 7N-11N BETWEEN 49W-52W. TROPICAL WAVE IS ALONG 58W/59W S OF 10N MOVING W 15-20 KT. WAVE IS MOVING INLAND OVER SOUTH AMERICA BUT STILL REMAINS EMBEDDED WITHIN A MOISTURE MAXIMUM ON THE TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED DEEP CONVECTION. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 10N13W 7N20W 2N35W 3N49W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 180 NM N OF THE ITCZ BETWEEN 38W-43W AND WITHIN 225 NM N OF THE ITCZ BETWEEN 43W-52W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 150 NM N OF THE ITCZ BETWEEN 29W-38W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE COVERS S GULF ANCHORED IN THE E PACIFIC REGION EXTENDING ACROSS MEXICO...THE BAY OF CAMPECHE AND THE YUCATAN PENINSULA S OF 24N GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND OVER MEXICO WITH SCATTERED SHOWERS MOVING OVER THE W GULF FROM 21N-25N W OF 94W. A SHORTWAVE UPPER TROUGH IS MOVING OUT OF E TEXAS TO OVER LOUISIANA COVERING THE NW GULF N OF 25N W OF 90W WITH A SURFACE TROUGH OVER E TEXAS. SCATTERED/ HEAVY SHOWERS WITH SCATTERED THUNDERSTORMS ARE N OF 29N TO INLAND OVER SE TEXAS AND W LOUISIANA BETWEEN 92W-95W AND N OF 29N ACROSS THE MISSISSIPPI DELTA TO OVER MISSISSIPPI COAST. SCATTERED SHOWERS...REMNANTS OF A SQUALL LINE ARE OVER THE GULF WATERS FROM 24N-28N BETWEEN 90W-93W. THE REMAINDER OF THE GULF WATERS CONTINUES TO BE DOMINATED BY A SECOND UPPER LEVEL RIDGE WITH THE AXIS OVER THE W ATLC GIVING THE GULF SW TO W UPPER FLOW. BROKEN TO OVERCAST HIGH CLOUDS COVER MOST OF THE GULF AGAIN TONIGHT WITH SOME FAST MOVING ISOLATED SHOWERS IN THE FLORIDA STRAITS FROM 23N-25N E OF 84W INCLUDING THE FLORIDA KEYS. THE SURFACE RIDGE REMAINS ANCHORED IN THE W ATLC BUT IS BEGINNING TO WEAKEN AND SHIFT EASTWARD AS A FRONTAL BOUNDARY APPROACHES THE NW GULF. CARIBBEAN SEA... THE UPPER RIDGE OVER THE S GULF OF MEXICO COVERS THE FAR NW CARIBBEAN W OF 82W WHILE A SECOND UPPER RIDGE ANCHORED IN THE TROPICAL ATLC COVERS THE E CARIBBEAN AND A NARROWING UPPER TROUGH IN THE CENTRAL CARIBBEAN THAT EXTENDS FROM OVER HAITI TO PANAMA. MODERATE SUBSIDENCE AND DRY STABLE AIR COVERS THE W AND CENTRAL CARIBBEAN LEAVING THE AREA W OF 75W MOSTLY CLEAR AGAIN TONIGHT. THE SURFACE RIDGE OVER THE W ATLC IS BEGINNING TO WEAKEN AND SHIFT EASTWARD THUS EASTERLY TRADE WINDS ARE EXPECTED TO WEAKEN. CONVERGENCE OF UPPER LEVEL FLOW AND THE SURFACE FLOW OVER THE SW CARIBBEAN IS GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS INLAND AND WITHIN 90 NM ALONG THE COAST OF NICARAGUA AND COSTA RICA. THE UPPER LEVEL FLOW OVER THE SE CARIBBEAN IS GIVING THE AREA E OF THE LINE FROM THE DOMINICAN REPUBLIC/HAITI BORDER TO NW COLOMBIA BROKEN/OVERCAST MULTILAYERED CLOUDS WITH ISOLATED SHOWERS INCLUDING THE LESSER ANTILLES AND PUERTO RICO. ATLANTIC OCEAN... A WEAK BROAD SURFACE RIDGE DOMINATES THE W ATLC ANCHORED BY A 1023 MB HIGH NEAR 29N69W LEAVING THE W ATLC UNDER DRY STABLE AIR AND THUS MOSTLY CLEAR SKIES AGAIN TONIGHT. AN UPPER TROUGH IS OVER THE E/CENTRAL ATLC N OF 23N E OF 45W SUPPORTING A DISSIPATING COLD FRONT THAT ENTERS THE REGION NEAR 32N38W EXTENDING TO 30N43W BECOMING DISSIPATING STATIONARY BOUNDARY TO 27N53W. A WEAK SURFACE TROUGH EXTENDS FROM 30N40W TO 25N51W WITH ISOLATED SHOWERS POSSIBLE WITHIN 60 NM EITHER SIDE OF THE TROUGH AXIS. A BROAD UPPER RIDGE THAT IS ANCHORED IN THE TROPICAL ATLC EXTENDS OVER THE CENTRAL ATLC ALONG 50W ALSO COVERING THE E CARIBBEAN. A SURFACE RIDGE DOMINATES THE E ATLC ANCHORED BY A 1030 MB HIGH NE OF THE AZORES. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE