000 AXNT20 KNHC 142347 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAY 14 2007 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...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 4N20W 4N40W 3N51W. A CLUSTER OF MODERATE CONVECTION IS ALONG 20W FROM 2N-5N. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE INLAND OVER SW AFRICA FROM 6N-11N BETWEEN 6W-11W. THE HOVMOLLER DIAGRAM SHOWS THE WESTWARD PROPAGATION OF THIS CONVECTIVE AREA OVER AFRICA DURING THE PREVIOUS DAYS. SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF BRAZIL WEST OF 40W AS WELL AS OVER FRENCH GUIANA AND SURINAME. ...DISCUSSION... GULF OF MEXICO... AS OF 21Z...A 1020 MB HIGH IS CENTERED OVER THE NW GULF OF MEXICO NEAR 27N94W. THIS SYSTEM IS PRODUCING 5-10 KT WINDS AND MOSTLY FAIR WEATHER. INFORMATION FROM NESDIS AND VIS SAT IMAGERY INDICATE THAT SMOKE IS STILL COVERING SOUTH FLORIDA AND THE KEYS AS WELL AS THE EASTERN PORTION OF THE GULF. DIURNAL HEATING AND THE TAIL END OF A FRONTAL BOUNDARY ACROSS CENTRAL FLORIDA HAVE FAVORED THE DEVELOPMENT OF SHOWERS AND TSTMS ACROSS THE SOUTH-CENTRAL PORTIONS OF THE STATE...INCLUDING ALSO THE FLORIDA KEYS. IN THE UPPER LEVELS...WLY FLOW DOMINATES MOST OF THE GULF WITH STRONG SUBSIDENCE. A SHORT-WAVE TROUGH OVER E TEXAS IS GENERATING SOME SHOWER/TSTM ACTIVITY OVER TEXAS AND SE LOUISIANA. WEAK HIGH PRES OVER THE NW GULF WILL DISSIPATE LATE TONIGHT WHILE HIGH PRESSURE JUST OFF THE MID ATLANTIC COAST BUILDS IN GIVING THE AREA A MODERATE TO FRESH ELY WIND FLOW. CARIBBEAN SEA... A 1008 MB LOW IS CENTERED OVER THE SW CARIBBEAN JUST OFF THE COLOMBIAN COAST. A SURFACE TROUGH EXTENDS MAINLY N FROM THE LOW TOWARDS THE CAYMAN ISLANDS/CENTRAL CUBA. THIS FEATURE IS GENERATING AN AREA OF MODERATE TO ISOLATED STRONG CONVECTION JUST SOUTH OF JAMAICA WHERE SOME SHOWERS HAVE BEEN REPORTED. THIS TROUGH WILL REMAIN NEARLY STATIONARY DURING THE NEXT FEW DAYS. NLY WINDS ARE FOUND WEST OF THE TROUGH AXIS OVER THE WESTERN CARIBBEAN WHILE MODERATE TRADE WINDS DOMINATE THE REMAINDER OF THE BASIN. TRADES ARE EXPECTED TO INCREASE ACROSS THE E-CENTRAL CARIBBEAN BEGINNING TOMORROW AS HIGH PRES BUILDS N OF THE AREA. ALOFT...AN E/W RIDGE EXTENDS OVER NORTHERN SOUTH AMERICA/CENTRAL AMERICA INTO THE EPAC WITH AXIS ALONG 10N. WLY UPPER LEVEL FLOW IS N OF THE RIDGE AXIS DOMINATING THE CARIBBEAN SEA. THE GFS MODEL FORECASTS A CLOSED LOW TO FORM ALONG THE TROUGH AXIS NEAR THE CAYMAN ISLANDS ON WED...THEN MOVES IT N ACROSS CENTRAL CUBA ON THU. WILL WAIT FOR LATER MODEL RUNS BEFORE MAKING ANY DETERMINATION AS TO WHETHER THIS SCENARIO OCCURS. ATLANTIC... A BACK DOOR COLD FRONT ENTERS THE DISCUSSION AREA NEAR 31N60W THEN CONTINUES MAINLY WWD ENTERING THE FLORIDA PENINSULA NEAR TITUSVILLE. A NARROW BAND OF LOW/MID CLOUDS WITH ISOLATED SHOWERS IS RELATED TO THE FRONT. A SURFACE TROUGH IS AHEAD OF THE FRONT AND ALSO EXTENDS SW TO THE BAHAMAS ALONG 26N65W 23N72W. SCATTERED SHOWERS ARE WITHIN 70 NM OF THE TROUGH. ANOTHER SURFACE TROUGH IS FURTHER E ALONG 29N58W 25N60W. AN AREA OF CLOUDINESS WITH EMBEDDED SHOWERS/ISOLATED IS MOSTLY E OF THE TROUGH FROM 23N-31N BETWEEN 50W-58W. A 1032 MB HIGH IS CENTERED OVER THE E ATLANTIC NEAR THE AZORES. A SURFACE RIDGE AXIS EXTENDS SW TO THE LEEWARD ISLANDS. ACCORDING TO THE 14/1800 UTC SAHARAN AIR LAYER FROM CIMSS...A BROAD AREA OF AFRICAN DUST EXTENDS FROM THE LESSER ANTILLES ALL THE WAY E TO AFRICA WITH AN SECONDARY THICKER PLUME OF DUST S OF 15N AND E OF 42W MOVING W. ALOFT...A TROUGH/RIDGE/TROUGH PATTERN COVERS THE AREA. A BROAD TROUGH IS OVER THE W ATLANTIC N OF 26N W OF 60W SUPPORTING THE BACK DOOR COLD FRONT. A RIDGE IS OVER THE CENTRAL ATLANTIC N OF 20N BETWEEN 45W-60W. A TROUGH IS OVER THE E ATLANTIC N OF 10N BETWEEN 30W-45W. WLY FLOW IS E OF 30W. $$ GR