000 AXNT20 KNHC 290552 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUN 29 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 0515 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 30W S OF 12N MOVING W NEAR 10-15 KT. THE WAVE REMAINS EMBEDDED WITHIN THE ITCZ WITH LITTLE SIGNIFICANT DEEP CONVECTION. ONLY SCATTERED SHOWERS FROM 4N-6N BETWEEN 27W AND THE WAVE AXIS. A TROPICAL WAVE IS ALONG 39W S OF 13N MOVING W NEAR 10-15 KT. A BROAD AREA OF LOW-MID LEVEL CIRCULATION IS EVIDENT ON SATELLITE IMAGERY FROM 8N-12N BETWEEN 35W-40W. ISOLATED MODERATE CONVECTION IS WITHIN 200 NM ON EITHER SIDE OF THE WAVE AXIS. A TROPICAL WAVE IS ALONG 55W S OF 12N MOVING W NEAR 15 KT. A LOW-AMPLITUDE INVERTED-V SIGNATURE IS OBSERVED ON SATELLITE IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 6N-9N WITHIN 200 NM E OF THE WAVE AXIS. THIS CONVECTION IS LIKELY EMBEDDED WITHIN THE ITCZ. A WEAK TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 71W FROM THE DOMINICAN REPUBLIC TO WRN VENEZUELA MOVING W NEAR 15 KT. WAVE IS UNDER UPPER SWLY FLOW AND DIVERGENCE ALOFT. THIS IS ENHANCING SCATTERED MODERATE CONVECTION WEST OF THE WAVE AXIS OVER WRN VENEZUELA AND NRN COLOMBIA. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 8N12W 8N29W 9N32W 8N38W 7N40W 5N45W 7N54W AND INTO S AMERICA NEAR 6N57W. IN ADDITION TO CONVECTION ASSOCIATED WITH TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS WITHIN 90 NM OF A LINE FROM 10N18W TO 5N29W. SIMILAR CONVECTION IS FROM 1N-4N BETWEEN 38W-42W. ALSO SCATTERED MODERATE CONVECTION IS WITHIN 90 NM ON EITHER SIDE OF THE WAVE AXIS BETWEEN 49W-54W. ...DISCUSSION... GULF OF MEXICO... AN UPPER-LEVEL LOW REMAINS POSITIONED OFF THE S TEXAS COAST COVERING THE WESTERN GULF. AN UPPER HIGH CENTERED ACROSS THE GULF OF HONDURAS IN THE NW CARIBBEAN SEA EXTENDS A RIDGE OVER THE CENTRAL AND EASTERN GULF INCLUDING THE FLORIDA PENINSULA. SWLY FLOW BETWEEN THESE UPPER FEATURES IS ADVECTING A DEEP LAYER OF TROPICAL MOISTURE FROM THE E PACIFIC INTO THE REGION. THE DIFFLUENT PATTERN OF THIS FLOW IS ENHANCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS SRN MEXICO AND THE BAY OF CAMPECHE S OF 20N. ONLY OTHER AREA OF CONVECTIVE ACTIVITY TO NOTE IS SCATTERED SHOWERS AND TSTMS MOVING ACROSS THE WRN FLORIDA PANHANDLE AND ADJACENT COASTAL GULF WATERS. AT THE SURFACE A HIGH PRESSURE RIDGE EXTENDS FROM THE CENTRAL ATLC OVER CENTRAL FLORIDA AND ACROSS THE GULF MAINTAINING S-SE 10-15 KT RETURN FLOW OVER THE CENTRAL AND WESTERN PORTIONS OF THE GULF. CARIBBEAN... AN UPPER-LEVEL RIDGE/TROUGH/RIDGE PATTERN COVERS THE CARIBBEAN. DIVERGENCE ALONG THE SRN EXTENT OF THE RIDGE OVER THE NW CARIBBEAN COUPLED WITH LOW-LEVEL WIND SPEED CONVERGENCE IS GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WITHIN 100 NM OF THE COASTS OF PANAMA...COSTA RICA AND NICARAGUA. STRONG SUBSIDENCE ALONG THE BASE OF THE UPPER TROUGH EXTENDING ACROSS HISPANIOLA IS INHIBITING DEEP CONVECTION IN THE CENTRAL CARIBBEAN BETWEEN 70W-82W. DIVERGENT FLOW E OF THE TROUGH IS ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE ERN CARIBBEAN AND LESSER ANTILLES INCLUDING PUERTO RICO AND THE US/UK VIRGIN ISLANDS. A STRONG SURFACE RIDGE OVER THE CENTRAL ATLC CONTINUES TO PROVIDE STRONG EASTERLY TRADES THROUGHOUT THE CARIBBEAN. ATLANTIC... UPPER-LEVEL DIVERGENCE IS GENERATING AN AREA OF SCATTERED SHOWERS IN THE W ATLC N OF 25N AND W OF 77W. ISOLATED TSTMS ARE EMBEDDED WITHIN THIS AREA OF SHOWERS NORTH OF GRAND BAHAMA ISLAND. SWLY UPPER FLOW BETWEEN AN UPPER TROUGH CENTERED NEAR 23N66W OVER THE W ATLC AND AN UPPER RIDGE CENTERED NEAR 13N52W EAST OF THE WINDWARD ISLANDS IS ADVECTING DEEP-LAYER MOISTURE INTO THE TROPICAL N ATLC W OF 52W. THE REMAINDER OF THE DISCUSSION AREA IS DOMINATED BY A VERY STABLE SURFACE RIDGE ANCHORED BY A STATIONARY 1030 MB HIGH PRESSURE CENTERED NEAR 35N37W SW OF THE AZORES. THIS RIDGE IS MAINTAINING MODERATE EASTERLY FLOW THROUGHOUT THE ERN AND CENTRAL ATLC. ALOFT... UPPER LEVEL DIVERGENCE IS ENHANCING CONVECTION ALONG THE ITCZ. $$ HUFFMAN