000 AXNT20 KNHC 171034 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT MAY 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 32W S OF 11N MOVING W 10 KT. WEAK INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY. ANY SHOWERS/CONVECTION ARE ASSOCIATED WITH THE ITCZ. TROPICAL WAVE IS ALONG 52W/53W S OF 11N MOVING W 5-10 KT. WAVE SIGNATURE IS DISTORTED AS IT MOVES INLAND OVER SOUTH AMERICA WITH NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IN THE SW CARIBBEAN ALONG 78W S OF 10N MOVING W NEAR 10 KT. NO WAVE SIGNATURE IS OBSERVED AND IS NOT INDICATED BY THE PRECIPITABLE WATER IMAGERY. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE INLAND AND ALONG THE IMMEDIATE COAST OF COLOMBIA AND PANAMA FROM 76W TO 79W. ..THE ITCZ... ITCZ AXIS IS CENTERED ALONG 6N8W 5N12W 6N27W 4N41W 4N51W. CLUSTERS OF SCATTERED MODERATE/STRONG TO SCATTERED/NUMEROUS STRONG CONVECTION ARE FROM 6N TO S OF THE EQUATOR E OF 14W ACROSS THE PRIME MERIDIAN. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF LINE FROM 4N16W TO 9N15W WITH CLUSTERS OF SIMILAR CONVECTION FROM 1N-5N BETWEEN 41W-48W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 180/200 NM OF THE ITCZ AXIS BETWEEN 21W-41W. ...DISCUSSION... GULF OF MEXICO... A WEAK COLD FRONT EXTENDS OFF THE SE US COAST OVER THE FLORIDA PANHANDLE JUST W OF JACKSONVILLE INTO THE GULF TO NEAR 27N88W WHERE IT BECOMES NEAR STATIONARY INTO MEXICO NEAR TUXPAN. THE UPPER LEVEL TROUGH AND THUS THE SUPPORT FOR THIS FRONT IS WELL N OF THE AREA. THE UPPER LEVELS OF THE GULF ARE DOMINATED BY A BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN AND ALSO COVERS THE W ATLC. HEAVY SHOWERS AND THUNDERSTORMS CONTINUE INLAND OVER CENTRAL MEXICO WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS MOVING INTO THE NW GULF BY THE UPPER LEVEL FLOW FROM TAMPICO MEXICO TO HOUSTON TEXAS W OF 95W. OTHERWISE ISOLATED SHOWERS ARE W OF THE FRONT WHILE THE SE GULF REMAINS CLOUD FREE. HOWEVER...SMOKE REMAINS OVER PORTIONS OF THE GULF AS A RESULT OF FIRES THAT WHERE OVER MEXICO AND THE YUCATAN. CARIBBEAN SEA... BROAD UPPER RIDGE IS ANCHORED OVER NEAR THE CAYMAN ISLANDS AND COVERS THE CARIBBEAN W OF 65W AND EXTENDS OVER THE GULF OF MEXICO AND THE W ATLC. THIS IS PRODUCING STRONG SUBSIDENCE AND DRY STABLE AIR OVER MOST OF THE AREA THUS LIMITING ANY DEEP CONVECTION. A SURFACE TROUGH...REMNANTS OF A FRONTAL BOUNDARY... EXTENDS ACROSS THE VIRGIN ISLANDS...PUERTO RICO...S HISPANIOLA...AND N JAMAICA TO NEAR 18N80W. SCATTERED SHOWERS ARE WITHIN 75 NM OF THIS BOUNDARY. WESTERLY UPPER FLOW AND THUS HIGH CLOUDS COVERS THE S CARIBBEAN S OF A LINE FROM CENTRAL NICARAGUA ALONG N COLOMBIA AND THE ABC ISLANDS THEN NE OVER THE LESSER ANTILLES JUST S OF GUADELOUPE. ATLANTIC OCEAN... DEEP LAYERED RIDGE COVERS THE THE W ATLC WITH THE UPPER RIDGE ANCHORED IN THE CARIBBEAN AND THE SURFACE RIDGE ANCHORED BY A 1019 MB HIGH NEAR 26N61W. DEEP LAYERED TROUGH IS IN THE CENTRAL ATLC WITH THE UPPER TROUGH N OF 22N BETWEEN 40W-53W AND THE WEAKENING COLD FRONT ENTERING THE REGION NEAR 32N46W TO 22N55W WHERE IT BECOMES A SURFACE TROUGH ACROSS THE VIRGIN ISLANDS INTO THE N CARIBBEAN. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 200 NM E OF THE FRONT N OF 27N. THE REMAINDER OF THE ATLC IS UNDER ZONAL WESTERLY FLOW WITH AN UPPER TROUGH DIPPING S TO OVER THE CANARY ISLANDS. A SURFACE RIDGE DOMINATES THE REMAINDER OF THE ATLC N OF 15N E OF THE CENTRAL ATLC FRONT WITH A 1024 MB HIGH CENTERED SW OF THE AZORES NEAR 33N31W AND THUS FAIR WEATHER CLOUDS ARE ALL THAT ARE PRESENT. $$ WALLACE