000 AXNT20 KNHC 301743 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN JUL 30 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 50W/51W SOUTH OF 15N. A 1012 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 11N51W. WIDELY SCATTERED MODERATE CONVECTION IS ASSOCIATED WITH THE LOW/WAVE. ALTHOUGH CONDITIONS ARE CURRENTLY ONLY MARGINALLY FAVORABLE FOR DEVELOPMENT...THIS SYSTEM STILL HAS THE POTENTIAL TO BECOME A TROPICAL DEPRESSION OVER THE NEXT COUPLE OF DAYS AS IT MOVES WEST-NORTHWESTWARD AT 15 TO 20 MPH. ...TROPICAL WAVES... A SECOND TROPICAL WAVE IS ALONG 75W SOUTH OF 21N MOVING WEST AROUND 20 KT. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ARE ON EITHER SIDE OF THE WAVE AXIS FROM 15N-18N BETWEEN 71W-80W. THE WAVE IS MOVING AWAY FROM PUERTO RICO AND THE VIRGIN ISLANDS... BUT AN AREA OF MODERATE SHOWERS WITH EMBEDDED TSTMS REMAINS OVER THE NORTHEASTERN CARIBBEAN SEA...HISPANIOLA... PUERTO RICO...AND THE VIRGIN ISLANDS. THIS CONVECTIVE ACTIVITY IS NOW ASSOCIATED WITH A SURFACE TROUGH THAT CROSSES THE ENCHANTED ISLAND. EARLIER THIS MORNING...SAN JUAN REPORTED 2.78 INCHES OF RAIN. THIS SYSTEM HAS BECOME A LITTLE BETTER ORGANIZED THIS MORNING AND SOME SLOW DEVELOPMENT IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS IT MOVES WEST-NORTHWESTWARD AT 10 TO 15 MPH. THE THIRD TROPICAL WAVE IS INLAND OVER THE YUCATAN PENINSULA AND GUATEMALA ALONG 90W SOUTH OF 20N MOVING WEST 20 KT. MOST OF THE CONVECTIVE ACTIVITY RELATED TO THE WAVE IS ON THE PACIFIC SIDE. THIS TROPICAL WAVE WILL MOVE THROUGH THE BAY OF CAMPECHE THIS AFTERNOON AND TONIGHT. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N14W 8N30W 13N45W 9N52W 8N60W. A CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION HAS MOVED OFF THE WEST COAST OF AFRICA PROBABLY ASSOCIATED WITH A TROPICAL WAVE. SHOWERS AND THUNDERSTORMS EXIST FROM 6N-12N BETWEEN 16W-20W. SCATTERED MODERATE CONVECTION IS WITHIN 40/60 NM ON EITHER SIDE OF THE ITCZ AXIS FROM 24W-30W AND FROM 38W-45W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER RIDGE EXTENDS ALONG THE NORTHERN GULF WATERS AND THE SOUTHEASTERN U.S.. TWO UPPER LEVEL LOW CENTERS REMAINS OVER THE AREA...ONE IS OVER THE N-CENTRAL GULF WHILE THE SECOND ONE HAS MOVED INLAND OVER NE MEXICO. AN UPPER LEVEL HIGH IS OVER THE BAY OF CAMPECHE COVERING SOUTH MEXICO...THE NW CARIBBEAN AND NORTHERN CENTRAL AMERICA. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS DOT THE NORTHERN HALF OF THE GULF. SCATTERED SHOWERS ARE ALSO SEEN OVER THE BAY OF CAMPECHE. MODERATE SUBSIDENCE DOMINATES THE SE GULF. A 1018 MB SURFACE HIGH IS OVER THE SE U.S. 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 AREA OF SHOWERS AND TSTMS OVER THE NORTHEASTERN CARIBBEAN SEA...HISPANIOLA...PUERTO RICO...AND THE VIRGIN ISLANDS ASSOCIATED WITH A SURFACE TROUGH. SEE TROPICAL WAVES SECTION. A RIDGE EXTENDS ACROSS THE NW CARIBBEAN AND NORTHERN CENTRAL AMERICA FROM AN UPPER LEVEL HIGH LOCATED OVER THE BAY OF CAMPECHE. ANOTHER UPPER LEVEL HIGH IS OVER THE LEEWARD ISLANDS...ENHANCING THE DEVELOPMENT OF THE CONVECTIVE ACTIVITY RELATED TO THE ABOVE MENTIONED SURFACE TROUGH. THIS RIDGE HAS BECOME THE DOMINATING FEATURE ACROSS THE E/CENTRAL CARIBBEAN AND NORTHERN SOUTH AMERICA. AN UPPER TROUGH RUNS FROM A CUT-OFF LOW LOCATED NORTH OF THE BAHAMAS ACROSS CUBA AND THE CAYMAN ISLANDS TO A SECOND UPPER CYCLONE CENTERED OVER THE NW CARIBBEAN. ABUNDANT UPPER LEVEL MOISTURE COVERS MUCH OF THE CARIBBEAN SEA. MODERATE TO STRONG SUBSIDENCE COVERS CUBA AND THE CENTRAL BAHAMAS. 10-20 KT TRADE WINDS BLOW ACROSS THE AREA. THE ATLANTIC OCEAN... A SURFACE RIDGE GOES FROM 1021 MB HIGH PRESSURE CENTER LOCATED NEAR 27N-60W TO NORTH FLORIDA AND THE SE U.S. WHERE THERE IS A SECONDARY CENTER WITH A CENTRAL PRESSURE VALUE OF 1018 MB. SCATTERED PATCHES OF LOW LEVEL CLOUDS ARE FROM 20N-30N EAST OF 60 W. WIDELY SCATTERED SHOWERS ARE OVER THE E ATLC N OF 26N WEST OF 75W. IN THE UPPER LEVELS...MIDDLE/UPPER LEVEL LOW CENTER IS JUST NORTH OF THE BAHAMAS NEAR 25N74W. A HIGH IS OVER THE LEEWARD ISLANDS NEAR 18N63W. AN UPPER RIDGE EXTENDS OVER THE E/CENTRAL ATLC FROM A HIGH ANCHORED OVER THE WEST COAST OF AFRICA NEAR 17N16W. THE RIDGE AXIS IS ALONG 19/20N. MODERATE TO STRONG SUBSIDENCE IS FOUND OVER THE ATLC FROM 20N-30N EAST OF 50W. $$ GR