000 AXNT20 KNHC 241056 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUL 24 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...TROPICAL WAVES... HIGH AMPLITUDE TROPICAL WAVE IS ALONG 42W S OF 24N MOVING WEST NEAR 15 KT. A 1011 MB LOW IS ON THE WAVE AXIS NEAR 14N. THIS WAVE AND LOW REMAIN WELL-DEFINED WITH A LOW LEVEL ROTATION OBSERVED ON SATELLITE IMAGERY AND IN THE SURROUNDING SHIPS/BUOYS. HOWEVER...THIS FEATURE CONTINUES TO BE VOID OF ANY SIGNIFICANT CONVECTION. A FEW SHOWERS ARE SPIRALING ON THE NORTHERN SEMICIRCLE OF THE SFC LOW AND AT THE BASE OF THE WAVE WITHIN 300 NM EITHER SIDE OF THE AXIS S OF 10N. THIS WAVE WILL LIKELY INCREASE IN FORWARD SPEED OVER THE NEXT COUPLE OF DAYS AS IT TRACKS UNDER A STRONG LOW-LEVEL RIDGE. TROPICAL WAVE IS ALONG 65W S OF 18N MOVING WEST NEAR 20 KT. THIS WAVE IS RATHER WEAK AND LOW AMPLITUDE. WAVE REMAINS EMBEDDED WITHIN AN AREA OF DENSE SAHARAN DUST LIMITING ANY ORGANIZED SHOWER ACTIVITY. TROPICAL WAVE IS ALONG 77W/78W S OF 21N MOVING WEST NEAR 20 KT. THIS WAVE IS ALSO RATHER WEAK WITH LITTLE ASSOCIATED CONVECTION. ONLY A HINT OF SOME EVIDENCE OF A WAVE-LIKE STRUCTURE IS EVIDENT ON SATELLITE IMAGERY. TROPICAL WAVE IS ALONG 100W S OF 21N MOVING WEST 5-10 KT. THIS WAVE IS INTERACTING WITH A BROAD UPPER RIDGE OVER MEXICO TO PRODUCE DISORGANIZED SHOWERS AND TSTMS ACROSS S MEXICO AND THE SW GULF. UPPER-LEVEL WINDS ARE EXPECTED TO BECOME A LITTLE MORE FAVORABLE FOR DEVELOPMENT DURING THE NEXT DAY OR TWO AS THE WAVE MOVES SLOWLY NORTHWESTWARD. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N14W 10N30W 14N39W 10N49W TO INLAND OVER SOUTH AMERICA NEAR 8N59W. THE ITCZ IS RELATIVELY QUIET WITH ONLY SCATTERED SHOWERS AND TSTMS WITHIN 120 NM EITHER SIDE OF THE AXIS E OF 16W AND W OF 43W. ...DISCUSSION... GULF OF MEXICO... A COMPLEX UPPER LEVEL PATTERN LIES ABOVE THE GULF OF MEXICO. A WEAK UPPER HIGH IS CENTERED OFF THE FLORIDA COASTLINE N OF THE BAHAMAS NEAR 29N78W SOUTH OF AN UPPER TROUGH ACROSS THE MID-ATLANTIC STATES. AN UPPER LOW IS IN THE SE GULF NEAR 25N85W. ANOTHER ELONGATED UPPER LOW IS IN THE NW GULF NEAR 28N95W AND A BROAD RIDGE COVERS S MEXICO AND THE BAY OF CAMPECHE. THIS PATTERN IS PRODUCING AN ABUNDANT AMOUNT OF MOISTURE IN THE REGION. SCATTERED SHOWERS ARE OCCURRING ACROSS THE AREA. THE MOST CONVECTIVE WEATHER EXISTS IN THE W GULF AND OVER S MEXICO W OF 89W S OF 26N ENHANCED BY A TROPICAL WAVE ALONG 100W. EVEN THOUGH THERE IS A FAIR AMOUNT OF CONVECTION IN THIS AREA IT REMAINS DISORGANIZED. AN ILL-DEFINED SFC TROUGH IS EMBEDDED IN THIS UNSETTLED WEATHER ALONG 95W FROM 21N-26N. A FEW CLUSTERS OF SHOWERS AND TSTMS THAT FIRED UP OVERNIGHT IN THE STRAITS OF FLORIDA ARE WEAKENING. AT THE SURFACE...RIDGING IS BUILDING EASTWARD FROM A STRONG WEST/CENTRAL ATLC HIGH. A STATIONARY FRONT LIES JUST TO THE N OF THE AREA ACROSS THE GULF COAST STATES ENHANCING A FEW SHOWERS AND TSTMS FROM TEXAS TO THE FLORIDA PANHANDLE. COMPUTER MODELS KEEP A FAIR AMOUNT OF MOISTURE IN THE W GULF TODAY AND TOMORROW...BUT SHOW A GRADUAL DRYING TREND IN THE EAST AND CENTRAL GULF DURING THE EARLY PART OF THE WEEK. CARIBBEAN SEA... TWO WEAK LOW AMPLITUDE TROPICAL WAVES EXIST IN THE CARIBBEAN SEA. BOTH OF THESE WAVES ARE RATHER BENIGN FEATURES. FOR MORE DETAILS SEE THE TROPICAL WAVES SECTION ABOVE. A BROAD UPPER RIDGE EXTENDS FROM MEXICO ACROSS CENTRAL AMERICA. A CONSIDERABLE AMOUNT OF MOISTURE IS ASSOCIATED WITH THE RIDGE WEST OF 82W. UPPER DIFFLUENCE IS GENERATING PATCHES OF MODERATE CONVECTION OVER HONDURAS...GUATEMALA AND BELIZE. SIMILAR PATCHES OF CONVECTION IS OCCURRING OVER COLOMBIA AND PANAMA ASSOCIATED WITH THE ITCZ. SCATTERED SHOWERS EXTEND FROM THE CAYMAN ISLANDS TO THE BAHAMAS GENERATED BY UPPER DIFFLUENT FLOW BETWEEN AN UPPER HIGH E OF N FLORIDA AND AN UPPER LOW IN THE SE GULF. AN UPPER LEVEL TROUGH COVERS THE CENTRAL CARIBBEAN WITH THE AXIS EXTENDING FROM HAITI TO NEAR 14N81W. DRY/STABLE AIR ACCOMPANIES THE TROUGH. MAINLY FAIR WEATHER COVERS THE CENTRAL AND EASTERN CARIBBEAN. THE ONLY AREA OF CLOUDINESS IS DRIVEN BY UPPER LEVEL SOUTHERLY WINDS ON THE EAST SIDE OF THE TROUGH AXIS WHICH IS DRAWING BROKEN MID-UPPER LEVEL MOISTURE FROM THE ITCZ NWD TO 16N BETWEEN 62W-75W. MODERATE TO STRONG TRADE WINDS ARE OCCURRING ACROSS THE CARIBBEAN. THESE WINDS WILL REMAIN RATHER STRONG FOR THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... UPPER DIFFLUENCE BETWEEN A LARGE BUILDING AMPLIFIED ATLC RIDGE AND TROUGH OFF THE MID-ATLANTIC STATES IS PRODUCING A FAIR AMOUNT OF MOISTURE W OF 61W MOSTLY N OF 24N. SCATTERED SHOWERS ARE EMBEDDED IN THIS MOISTURE PLUME. A PATCH OF MODERATE CONVECTION HAS DEVELOPED FROM 23N-26N BETWEEN 61W-64W. THE WEST ATLC RIDGE COVERS THE AREA W OF 40W. A LARGE UPPER RIDGE EXTENDS FROM W AFRICA OUT TO 30W. AN UPPER TROUGH COVERS THE REGION BETWEEN THE RIDGES...30W-40W...N OF 25N. ESSENTIALLY DRY STABLE AIR COVERS MUCH OF THE AREA E OF 61W. AT THE SURFACE...HIGH PRES IS THE THEME WITH A 1027 MB HIGH CENTERED NEAR 34N54W. MOSTLY FAIR WEATHER WITH ONLY SCATTERED PATCHES OF CLOUDS AND ISOLATED SHOWERS LIES UNDER THE RIDGE EAST OF 61W. ACCORDING TO THE 09 UTC SAHARAN AIR LAYER ANALYSIS FROM UW-CIMSS...SAHARAN DUST IS DENSE OUT TO 40W WITH A FAIR AMOUNT OF IT SPREADING ACROSS THE CARIBBEAN AND ATLANTIC TO ABOUT 70W. $$ CANGIALOSI