000 AXNT20 KNHC 291749 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT JUL 29 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURE... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 43W/44 SOUTH OF 15N MOVING WEST 20 KT. A 1011 MB LOW PRESSURE CENTER IS ALONG THE WAVE FROM 8N TO 9N. ONLY ISOLATED MODERATE CONVECTION IS ASSOCIATED WITH THE LOW/WAVE. WHILE THE ASSOCIATED SHOWER ACTIVITY HAS DECREASED THIS MORNING...THERE IS STILL POTENTIAL FOR DEVELOPMENT...AND A TROPICAL DEPRESSION COULD FORM DURING THE NEXT DAY OR TWO AS THE SYSTEM MOVES WESTWARD AT ABOUT 20 MPH. ...TROPICAL WAVES... VERY ACTIVE TROPICAL WAVE IS ALONG 66W/67W SOUTH OF 20N MOVING WEST 20 KT. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ARE FROM 14N-18N BETWEEN 65W-72W. THE WAVE IS CURRENTLY MOVING ACROSS PUERTO RICO AND WILL CROSS DOMINICAN REPUBLIC THIS AFTERNOON AND TONIGHT...BRINGING AN INCREASE IN SHOWER AND TSTM ACTIVITY TO THAT AREA. THE WAVE IS ALSO HELPING TO ENHANCE THE SHOWER/TSTM ACTIVITY OVER WESTERN VENZUELA. GUADELOUPE IN THE LESSER ANTILLES REPORTED 1.92 INCHES OF RAIN WITH THE PASSAGE OF THE TROPICAL WAVE WHILE THE SAN JUAN DOPPLER RADAR ESTIMATED RAINFALL AMOUNTS OF 2 TO 3 INCHES OVER ST. CROIX IN THE U.S. VIRGIN ISLANDS EARLY THIS MORNING. ALTHOUGH SHOWER ACTIVITY HAS INCREASED THIS MORNING IN ASSOCIATION WITH THIS TROPICAL WAVE THERE ARE NO SIGNS OF ORGANIZATION...AND ADDITIONAL DEVELOPMENT...IF ANY...SHOULD BE SLOW TO OCCUR. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 82W/83W SOUTH OF 21N MOVING WEST 20 KT. WIDELY SCATTERED MODERATE CONVECTION IS JUST AHEAD OF THE WAVE AXIS OVER THE NW CARIBBEAN AND THE GULF OF HONDURAS. A CLUSTER OF SCATTERED MODERATE CONVECTION IS OVER THE SW CARIBBEAN BEHIND THE WAVE AXIS FROM 11N-13N BETWEEN 79W-81W. SHOWERS AND THUNDERSTORMS ARE SOUTH OF 10N IN THE GULF OF URABA OF COLOMBIA...PROBABLY MORE RELATED TO THE ITCZ THAN TO THIS WAVE. THIS FEATURE IS EXPECTED TO ENHANCE THE SHOWER/TSTM ACTIVITY OVER N CENTRAL AMERICA THIS AFTERNOON AND TONIGHT. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 13N17W 12N-30W 9N43W 7N58W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG THE COAST OF W AFRICA AND THE COASTAL WATERS FROM 5N-13N. SIMILAR CONVECTION IS WITHIN 80/100 NM NORTH OF THE ITCZ AXIS BETWEEN 47W-55W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER RIDGE EXTENDS ALONG THE NORTHER GULF WATERS AND THE SE OF THE U.S. MIDDLE TO UPPER LEVEL LOW CENTERS ARE IN THE WESTERN PORTION OF THE BAY OF CAMPECHE AND OVER THE NE CORNER OF THE GULF. A SURFACE TROUGH...REFLECTION OF THE SECOND UPPER LOW RUNS FROM 27N-83W TO 23N-85W. SCATTERED SHOWERS WITH EMBEDDED TSTMS ARE ASSOCIATED WITH THE SURFACE TROUGH. SIMILAR CONVECTIVE ACTIVITY IS OVER THE W BAY OF CAMPECHE. A 1012 MB SURFACE HIGH IS OVER ALABAMA WITH A RIDGE EXTENDING WWD TO EASTERN TEXAS. BROAD 10-15 SELY FLOW DOMINATES THE GULF OF MEXICO. A RIDGE WILL PERSIST ACROSS THE NORTHERN GULF DURING THE NEXT FEW DAYS. THE CARIBBEAN SEA... THE MAIN FEATURE ACROSS THE BASIN IS THE TROPICAL WAVE AFFECTING PUERTO RICO AND DOMINICAN REPUBLIC. SEE TROPICAL WAVES SECTION. AN UPPER HIGH IS LOCATED OVER THE GULF OF HONDURAS WHILE ANOTHER ONE IS JUST EAST OF THE LEEWARD ISLANDS...SUPPORTING THE DEVELOPMENT OF THE CONVECTIVE ACTIVITY RELATED TO THE ABOVE MENTIONED TROPICAL WAVE. IN THE MIDDLE...THERE IS AN UPPER TROUGH THAT EXTENDS FROM A LOW LOCATED NORTH OF THE BAHAMAS TO OVER CUBA AND THE CAYMAN ISLANDS. CONSIDERABLE UPPER LEVEL MOISTURE COVERS THE CARIBBEAN SEA. 10-20 KT TRADE WINDS BLOW OVER MUCH OF THE AREA. THE ATLANTIC OCEAN... A SURFACE RIDGE GOES FROM 1021 MB HIGH PRESSURE CENTER LOCATED NEAR 33N-31W TO NORTH FLORIDA AND THE SE U.S. WHERE THERE IS A SECONDARY CENTER WITH THE SAME CENTRAL PRESSURE VALUE. SCATTERED PATCHES OF LOW LEVEL CLOUDS ARE FROM 20N-31N EAST OF 60 W. DOPPLER RADAR SHOWS SCATTERED SHOWERS WITH EMBEDDED TSTMS ACROSS SOUTH FLORIDA AND THE SURROUNDING COASTAL WATERS. IN THE UPPER LEVELS...MIDDLE/UPPER LEVEL LOW CENTER IS JUST NORTH OF THE BAHAMAS NEAR 25N74W. A HIGH IS JUST EAST OF THE LEEWARD ISLANDS NEAR 18N61W. AN UPPER RIDGE IS ALSO OVER THE E/CENTRAL ATLC...WITH THE RIDGE AXIS ALONG 20N. MODERATE TO STRONG SUBSIDENCE IS FOUND OVER MUCH OF THE ATLC N OF 15N EAST OF 60W. $$ GR