000 AXNT20 KNHC 042352 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU MAY 04 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... THE ITCZ IS FAIRLY ACTIVE WEST OF 20 W. ITS AXIS IS CENTERED ALONG 7N10W 2N20W EQ30W EQ50W. A CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION IS WITHIN AROUND 100 NM SOUTH OF THE AXIS BETWEEN 10W-14W. MODERATE/ISOLATED STRONG CONVECTION IS FOUND WITHIN 120-150 NM NORTH OF THE AXIS BETWEEN 21W-31W AND BETWEEN 39W-50W. SIMILAR CONVECTION HAS DEVELOPED ALONG THE NORTHERN COAST OF BRAZIL BETWEEN 44W-53W AS WELL AS OVER FRENCH GUIANA. ...DISCUSSION... THE GULF OF MEXICO... NEARLY ZONAL UPPER LEVEL FLOW COVERS THE GULF WITH MODERATE SUBSIDENCE. UPPER LEVEL MOISTURE IS BEING ADVECTED FROM THE EPAC ACROSS NORTH-CENTRAL MEXICO AND THE NW CORNER OF THE GULF AND ALSO ACROSS SOUTH MEXICO AND THE YUCATAN PENINSULA INTO THE NW CARIBBEAN AND CENTRAL CUBA. AT THE SFC...A 1019 MB HIGH PRESSURE CENTERED NEAR 28N85W REMAINS NEARLY STATIONARY OVER THE NE PORTION OF THE GULF. THIS FEATURE IS PRODUCING FAIR WEATHER ACROSS MUCH OF THE AREA AND THE STATE OF FLORIDA. SE WINDS OF 10-15 KT BLOW ACROSS THE REGION. SHOWERS/TSTMS HAS DEVELOPED ALONG THE SIERRA MADRE MOUNTAINS NORTH OF 23N. HIGH PRES WILL MOVE E THROUGH SAT. A WEAK COLD FRONT IS EXPECTED TO MOVE INTO NE GULF COAST LATE SAT...BRINGING THE NEXT CHANCE OF RAINFALL. THE CARIBBEAN SEA... A MID/UPPER RIDGE DOMINATES MOST OF THE BASIN...CENTRAL AMERICA AND NORTHERN SOUTH AMERICA. UPPER LEVEL MOISTURE IS ADVECTED FROM THE YUCATAN PENINSULA ACROSS THE NW CARIBBEAN AND CENTRAL CUBA. SIMILAR MOISTURE IS SPREADING NWD INTO THE CARIBBEAN SEA FROM THE CONVECTIVE ACTIVITY OVER NORTHERN SOUTH AMERICA. A DIFLUENT PATTERN ALOFT CONTINUES TO ENHANCE THIS TSTM ACTIVITY. A PLUME OF HIGH CLOUDS STRETCHES FROM THE SW CARIBBEAN NEWD ACROSS PUERTO RICO AND THE VIRGIN ISLANDS. THE SAN JUAN DOPPLER RADAR SHOWS LESSER AMOUNT OF SHOWERS OVER THE ISLANDS THAN THE PREVIOUS DAYS...THANKS TO THE PRESENCE OF A DRYER AIR MASS. AT THE SFC...A TROUGH EXTENDS FROM 15N65W NEWD ACROSS THE LEEWARD AND THE CENTRAL ATLANTIC TO 26N55W. A BAND OF MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS ARE WITHIN 150 NM EAST OF THE TROUGH AXIS. THIS TROUGH WILL SLOWLY DRIFT E DURING THE NEXT FEW DAYS. THE ATLANTIC OCEAN... A DEEP-LAYER TROUGH COVERS THE ATLANTIC WATERS NORTH OF 20N WEST OF 50W...WITH AN UPPER LOW NORTH OF THE AREA. THIS TROUGH SUPPORTS THE ATLC COLD FRONT WHICH EXTENDS ALONG 31N50W 26N54W. A SURFACE TROUGH CONTINUES FROM 26N54W TO THE LEEWARD ISLANDS. A BAND OF MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS ARE WITHIN 150 NM EAST OF THE TROUGH AXIS. MODERATE TO STRONG SUBSIDENCE IS SEEN FROM 24N-30N BETWEEN 56W-75W. A WLY JET OF 70-90 KT IS SOUTH OF THE UPPER LOW FROM 26N-30N BETWEEN 55W-70W. A MID/UPPER RIDGE DOMINATES THE ATLC BETWEEN 25W-50W...WHILE AN UPPER TROUGH IS OVER THE REMAINDER OF THE AREA. AT THE SFC...A 1024 MB HIGH CENTERED NEAR 31N34W DOMINATES THE ATLC EAST OF 50W. SCATTERED PATCHES OF LOW LEVEL MOISTURE ARE ONLY OBSERVED UNDER THE INFLUENCE OF THIS HIGH. A BAND OF HIGH CLOUDS RUNS ALONG 9N FROM SOUTH AMERICA ALL THE WAY EAST TO 20W. $$ GR