000 AXNT20 KNHC 231024 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUN 23 2008 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 56W/57W S OF 18N MOVING W NEAR 20 KT. BROAD LOW/MID LEVEL INVERTED-V CURVATURE IS NOTED ON SATELLITE IMAGERY WITH NO ASSOCIATED DEEP CONVECTION. ISOLATED SHOWERS COVER A BROAD AREA FROM 14N-19N BETWEEN 55W-63W INCLUDING THE LESSER ANTILLES. TROPICAL WAVE IS IN THE W CARIBBEAN ALONG 88W S OF 19N MOVING W 20-25 KT. SATELLITE IMAGERY SHOWS WEAK LOW/MID LEVEL INVERTED-V CURVATURE MOVING THROUGH THE GULF OF HONDURAS AND INLAND OVER CENTRAL AMERICA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 19N W OF 86W TO INLAND OVER THE YUCATAN PENINSULA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 11N13W 5N32W 8N55W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 120 NM ALONG THE COAST OF SW AFRICA S OF 11N W OF 10W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 180 NM N OF THE ITCZ FROM 18-26W...WITHIN 90/120 NM S OF THE ITCZ FROM 20W-23W...WITHIN 200 NM EITHER SIDE OF THE ITCZ FROM 32W-42W AND FROM 7N-12N BETWEEN 51W-61W. ...DISCUSSION... GULF OF MEXICO... UPPER TROUGH EXTENDS FROM OVER THE US INTO THE W/CENTRAL GULF ACROSS CENTRAL LOUISIANA TO S MEXICO AND THE BAY OF CAMPECHE ANCHORED BY AN UPPER LOW OVER THE GREAT LAKES AREA. AN UPPER LEVEL RIDGE EXTENDS FROM THE CARIBBEAN OVER THE REMAINDER OF THE GULF INTO THE W ATLC ACROSS THE N BAHAMA ISLANDS. THIS IS SUPPLYING MUCH OF THE GULF WITH W TO SW UPPER FLOW AND ABUNDANCE OF TROPICAL MOISTURE. SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 45/60 NM OF LINE FROM 28N88W TO THE FLORIDA PANHANDLE NEAR TALLAHASSEE AND IN THE BAY OF CAMPECHE S OF 20N. SMALL CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE REMAINDER OF THE GULF WHILE THE TEXAS COAST REMAINS CLEAR THIS MORNING. WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC OVER THE GULF CREATING A WEAK PRESSURE PATTERN AND PROVIDING LIGHT WINDS ACROSS THE REGION. CARIBBEAN... AN UPPER RIDGE ANCHORED IN THE E PACIFIC REGION EXTENDS ACROSS CENTRAL AMERICA AND W/CENTRAL CUBA INTO THE W ATLC COVERING THE AREA N OF 11N W OF 80W WHILE A SECOND UPPER RIDGE ANCHORED IN THE TROPICAL ATLC COVERS THE E CARIBBEAN. AN UPPER TROUGH IS BETWEEN THESE UPPER RIDGES EXTENDING FROM ACROSS THE CENTRAL ATLC OVER HISPANIOLA SW TO E PANAMA. UPPER LEVEL DIFFLUENCE IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS WITHIN 90 NM ALONG THE SE COAST OF CUBA FROM 74W-78W. THE ITCZ CROSSES THE S CARIBBEAN FROM COLOMBIA N OF PANAMA INTO THE E PACIFIC OVER COSTA RICA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE AREA S OF 13N W OF 74W TO INLAND OVER W COLOMBIA AND CENTRAL AMERICA. MODERATE/STRONG EASTERLY TRADE WINDS DOMINATE MOST OF THE CARIBBEAN DUE TO THE TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE OVER THE ATLC AND LOWER PRESSURE OVER SOUTH AMERICA AND ARE USHERING IN ISOLATED SHOWERS OVER THE E CARIBBEAN E OF 70W. ATLANTIC... NARROW UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS W/CENTRAL CUBA AND THE N BAHAMA ISLANDS TO NEAR 30N75W PROVIDING UPPER DIFFLUENCE AND GENERATING CLUSTERS OF SCATTERED SHOWERS/ THUNDERSTORMS OVER A THE AREA W OF A LINE FROM CENTRAL CUBA NEAR 22N79W TO BEYOND 32N72W AND ISOLATED CLUSTERS OF SIMILAR ACTIVITY FROM 22N-29N BETWEEN 66W-73W. THE MOST PROMINENT UPPER LEVEL FEATURE IS THE UPPER TROUGH THAT REMAINS ACROSS THE BASIN EXTENDING THROUGH 32N14W ACROSS THE CANARY ISLANDS THE W ALONG 26N32W 23N44W 22N60W THEN SW INTO THE CARIBBEAN OVER HISPANIOLA. A SURFACE RIDGE DOMINATES THE ENTIRE ATLC BASIN FROM AFRICA INTO THE GULF OF MEXICO ANCHORED BY A 1029 MB HIGH CENTERED NEAR 32N48W. MODERATE SUBSIDENCE AND A FAIR AMOUNT OF DRY STABLE AIR ALSO DOMINATES THE ATLC E OF 60W GIVING THE AREA FAIR WEATHER AGAIN THIS MORNING. BROAD E/W UPPER RIDGE DOMINATES THE TROPICAL ATLC FROM THE CAPE VERDE ISLANDS TO OVER THE E CARIBBEAN ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ WALLACE