000 AXNT20 KNHC 230518 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUL 23 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 34W/35W S OF 21N WITH A 1013 MB LOW ALONG THE WAVE NEAR 15N MOVING W 10-15 KT. BROAD LOW LEVEL SIGNATURE CURVATURE WITH A WELL DEFINED LOW CENTER ARE OBSERVED ON INFRARED SATELLITE IMAGERY. WAVE IS EMBEDDED WITH AN AREA OF DENSE AFRICAN DUST...THUS ONE ISOLATED THUNDERSTORMS IS CENTERED NEAR 14N37.5W AND NO OTHER ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 54W S OF 17N MOVING W 10-15 KT. WAVE CONTINUES TO WEAKEN AND HAS BECOME A VERY LOW AMPLITUDE WAVE AS OBSERVED ON INFRARED SATELLITE IMAGERY. WAVE REMAINS EMBEDDED WITHIN AN AREA OF DENSE AFRICAN DUST...THUS NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 68W/69W S OF 20N MOVING W 10-15 KT. WEAK LOW LEVEL SIGNATURE CURVATURE IS OBSERVED ON INFRARED SATELLITE IMAGERY. HOWEVER...DUE TO THE VERY DRY CONDITIONS...NO ASSOCIATED SHOWERS/CONVECTION IN THE CARIBBEAN WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION INLAND OVER VENEZUELA. TROPICAL WAVE IS ALONG 96W S OF 21N MOVING W 10 KT. WAVE IS MOSTLY OVER S MEXICO AND THE E PACIFIC REGION AS WELL AS BEING BENEATH AN UPPER RIDGE WHICH IS MASKING THE SATELLITE IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 75 NM OF LINE FROM THE BAY OF CAMPECHE NEAR 20N94W OVER MEXICO AND GUATEMALA BEYOND 17N91W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N10W 7N15W 14N28W 5N52W AND ACROSS PANAMA AND COSTA RICA IN THE E PACIFIC REGION. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS IN THE SW CARIBBEAN S OF 10N FROM 75W-82W TO INLAND OVER COLOMBIA AND PANAMA. CLUSTERS SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM OF THE ITCZ AXIS FROM 36W-55W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS IN THE E GULF NEAR 27N89W WITH AN UPPER TROUGH EXTENDING W TO INLAND OVER S TEXAS/NE MEXICO NEAR THE BORDER. A NARROWING UPPER RIDGE EXTENDS ALONG THE N GULF COAST PRECEDING THE APPROACHING DEEP LAYERED TROUGH NOW RESIDING OVER THE NE US. THE ASSOCIATED COLD FRONT REMAINS WELL INLAND OVER THE SE US...HOWEVER THE ASSOCIATED SCATTERED SHOWERS/THUNDERSTORMS ARE MOVING INTO THE GULF N OF 28N E OF LOUISIANA. A SECOND UPPER RIDGE IS COVERING THE S GULF S OF 24N W OF 87W ANCHORED OVER THE E PACIFIC NEAR A TROPICAL SYSTEM IN THAT BASIN. CONVECTION IN THE BAY OF CAMPECHE IS ASSOCIATED WITH THE TROPICAL WAVE. AN UPPER HIGH IS LOCATED ALONG THE SE COAST OF FLORIDA COVERING THE AREAS OF 28N E OF 83W. RIDGE IN THE FAR W ATLC AND FROM OVER CUBA THROUGH THE STRAITS OF FLORIDA. CARIBBEAN SEA... BROAD UPPER RIDGE IS OVER THE S GULF EXTENDS INTO THE W CARIBBEAN W OF 83W WITH A SECOND WEAK UPPER RIDGE EXTENDING FROM AN UPPER HIGH ALONG THE SE COAST OF FLORIDA TO OVER THE JAMAICA AND THE CAYMAN ISLANDS. AN UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS HISPANIOLA INTO THE SW CARIBBEAN. THIS SCENARIO IS GENERATING SCATTERED THUNDERSTORMS ALONG THE COAST OF HAITI... JAMAICA...AND CUBA FROM 17N-22N BETWEEN 72W-80W. CONVECTION IN THE SW CARIBBEAN IS ASSOCIATED WITH THE ITCZ AXIS OVER PANAMA AND COSTA RICA. STRONG TRADEWINDS CONTINUE ACROSS THE CARIBBEAN S OF 18N WITH GALE FORCE WINDS EXPECTED BY SUNDAY NIGHT. ATLANTIC OCEAN... WEAK UPPER HIGH IS CENTERED ALONG THE SE COAST OF FLORIDA NEAR 26N80W WITH THE UPPER RIDGE EXTENDING S OF 30N INTO THE CARIBBEAN W OF 70W INTO THE SE GULF OF MEXICO. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 25N-33N W OF 73W TO OVER THE SE US. UPPER TROUGH IN THE CENTRAL ATLC EXTENDS FROM AN UPPER LOW NEAR 29N63W SW INTO THE CARIBBEAN ACROSS HISPANIOLA. A SECOND UPPER TROUGH IS DIPPING INTO THE E/CENTRAL ATLC N OF 26N FROM 30-50W WITH THE ASSOCIATED COLD FRONT N OF THE REGION. UPPER RIDGE COVERS THE REMAINDER OF THE ATLC EXTENDING FROM OFF AFRICA NEAR 25N14W ALONG 24N28W TO NEAR 17N45W. BROAD SURFACE RIDGE DOMINATES THE ATLC GIVING THE AREA E OF 70W LITTLE IN THE WAY OF CLOUDS MUCH LESS SHOWERS. LARGE AREA OF DENSE SAHARAN DUST CONTINUES TO MOVE OFF THE COAST OF AFRICA REACHING THE EASTERN MOST CARIBBEAN ISLANDS MOSTLY S OF THE UPPER RIDGE AXIS. THIS IS SUPPRESSING CONVECTION AND POSSIBLE TROPICAL DEVELOPMENT AT THIS TIME. $$ WALLACE