000 AXNT20 KNHC 230506 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0415 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 54W S OF 18N MOVING W 20-25 KT. WAVE WAS RELOCATED BASED ON MIMIC-TPC ANIMATION AND BROAD INVERTED-V SATELLITE IMAGERY. NO ASSOCIATED DEEP CONVECTION. ISOLATED SHOWERS COVER A BROAD AREA FROM 13N-18N BETWEEN 50W-61W. THIS WAVE WILL BE BRINGING SCATTERED SHOWERS TO THE LESSER ANTILLES DURING THE NIGHT AND CONTINUE FOR THE NEXT DAY OR SO AS THE WAVE PASSES. TROPICAL WAVE IS IN THE W CARIBBEAN ALONG 86W S OF 19N MOVING W 20-25 KT. SATELLITE IMAGERY SHOWS WEAK LOW/MID LEVEL INVERTED-V CURVATURE MOVING THROUGH THE GULF OF HONDURAS. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 18N W OF 84W TO INLAND OVER CENTRAL AMERICA AND THE YUCATAN PENINSULA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 12N12W 5N32W 8N52W 8N50W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 180 NM OF THE THE ITCZ E OF 20W TO INLAND OVER SW AFRICA AND WITHIN 250 NM OF THE ITCZ FROM 31W-42W. SMALL CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE WITHIN 120/150 NM OF THE ITCZ FROM 20W-31W AND WITHIN 180 OF THE ITCZ FROM 52W TO INLAND OVER SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... SHORTWAVE UPPER TROUGH EXTENDS OVER THE W GULF EXTENDING FROM W LOUISIANA TO OVER MEXICO JUST N OF TAMPICO MEXICO. AN UPPER-LEVEL RIDGE EXTENDS FROM THE CARIBBEAN OVER THE E GULF INTO THE W ATLC OVER THE N BAHAMA ISLANDS. THIS IS SUPPLYING MUCH OF THE GULF WITH W TO SW UPPER FLOW AND ABUNDANCE OF TROPICAL MOISTURE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE REGION E OF A LINE FROM CENTRAL LOUISIANA TO NEAR TAMPICO MEXICO WHILE THE TEXAS COAST REMAINS CLEAR TONIGHT WITH THE HIGHEST CONCENTRATION OF THUNDERSTORMS OVER THE SE GULF. WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC OVER THE E GULF TO 85W CREATING A WEAK PRESSURE PATTERN AND IS 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 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 PANAMA. UPPER LEVEL DIFFLUENCE IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS ACROSS CUBA AND THE THROUGH THE YUCATAN CHANNEL N OF 21N W OF 79W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER HE S CARIBBEAN S OF 13N W OF 75W 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. ATLANTIC... NARROW UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS W/CENTRAL CUBA AND THE N BAHAMA ISLANDS TO NEAR 30N73W PROVIDING UPPER DIFFLUENCE AND GENERATING HEAVY SHOWERS/THUNDERSTORMS WITHIN 90 NM OF LINE FROM 27N76W ACROSS THE BAHAMAS INTO THE FLORIDA STRAITS TO 24N81W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE REMAINDER OF THE AREA W OF A LINE FROM 31N71W TO CUBA NEAR 22N79W. THE MOST PROMINENT UPPER LEVEL FEATURE IS THE UPPER TROUGH THAT REMAINS ACROSS THE BASIN EXTENDING THROUGH 32N15W ACROSS THE CANARY ISLANDS THE W ALONG 27N30W 24N50W23N61W THEN SW INTO THE CARIBBEAN OVER HISPANIOLA. A SURFACE RIDGE DOMINATES THE ENTIRE ATLC BASIN FROM AFRICA INTO THE E GULF OF MEXICO ANCHORED BY A 1029 MB HIGH CENTERED NEAR 32N45W. MODERATE SUBSIDENCE AND A FAIR AMOUNT OF DRY STABLE AIR ALSO DOMINATES THE ATLC E OF 70W GIVING THE AREA FAIR WEATHER AGAIN TONIGHT. 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 TROPICAL WAVE ALONG 54W AND THE ITCZ. $$ WALLACE