000 AXNT20 KNHC 162320 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON APR 16 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 2215 UTC. ...THE ITCZ... ITCZ AXIS EXTENDS FROM 8N11W 3N20W CROSSES THE EQUATOR AT 34W AND CONTINUES INTO SOUTH AMERICA NEAR 3S45W. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60NM OF THE AXIS BETWEEN THE AFRICAN COASTLINE AND 14W. ISOLATED MODERATE CONVECTION IS WITHIN 60 NM S OF THE AXIS BETWEEN 19W-21W. ...DISCUSSION... GULF OF MEXICO... A 1024 MB HIGH OVER SE LOUISIANA IS KEEPING A COLDER AND DRIER AIRMASS OVER THE GULF. A FAIRLY TIGHT PRES GRADIENT BETWEEN THIS SFC HIGH AND A STRONG 971MB LOW OVER THE NORTHEAST U.S. IS PRODUCING MODERATE TO STRONG NLY WINDS OVER THE E GULF AND THE FLORIDA PENINSULA. BROKEN FAIR WEATHER STRATOCUMULUS CLOUDS COVER THE W/CENTRAL GULF WHILE THE E GULF REMAINS MOSTLY CLEAR. ALOFT...A RIDGE IS BUILDING OVER THE GULF WHILE A SHARP SHORTWAVE TROUGH IS OVER THE SW US. THIS TROUGH WILL SUPPORT THE NEXT COLD FRONT THAT IS FORECAST TO MOVE INTO THE GULF FROM THE TEXAS COAST EARLY WED. A PLUME OF UPPER LEVEL MOISTURE ASSOCIATED WITH THE EPAC JETSTREAM EXTENDS NEWD ACROSS N MEXICO AND TEXAS. WINDS AND SEAS WILL SUBSIDE OVER THE GULF AS HIGH PRES MOVES SLOWLY EWD. CARIBBEAN SEA... THE STRONG COLD FRONT THAT ENTERED THE NW CARIBBEAN YESTERDAY HAS BECOME STATIONARY THROUGH MUCH OF THE CARIBBEAN. AS OF 21Z...THE COLD FRONT ENTERS THE FORECAST AREA NEAR 31N63W THEN CONTINUES SW ACROSS THE CENTRAL BAHAMAS AND E CUBA BECOMING STATIONARY NEAR 20N79W. A WELL DEFINED BAND OF LOW/MID CLOUDS WITH POSSIBLE SHOWERS IS ASSOCIATED WITH THE FRONT. THE FRONT IS FORECAST TO DISSIPATE IN THE NEXT 24-48 HOURS. WINDS BEHIND THE FRONT REMAIN NLY AT 15-20 KT. THE REMAINDER OF THE BASIN CONTINUES UNDER THE INFLUENCE OF A STRONG UPPER HIGH CENTERED NEAR 14N71W WITH ABUNDANT DRY AND STABLE AIR ALOFT. THE TRADES ARE LIGHT TO MODERATE ACROSS MUCH OF THE AREA DUE TO THE WEAK PRES GRADIENT. ATLANTIC OCEAN... THE STRONG COLD FRONT ACROSS THE WESTERN ATLC IS PRODUCING GALE FORCE WINDS AND HAZARDOUS MARINE CONDITIONS. AT 18Z SHIP OBSERVATIONS REPORTED WINDS 25-30 KT AHEAD OF AND BEHIND THE FRONT. A GALE WARNING IS IN EFFECT TONIGHT AND TUE IN THE SW N ATLC N OF 27N. THIS COLD FRONT IS ASSOCIATED WITH A STRONG LOW PRES SYSTEM THAT IS NOW CENTERED OVER LONG ISLAND. A DEEP LAYERED TROUGH OVER THE FAR WEST ATLC IS SUPPORTING THIS FRONTAL SYSTEM. THE MID/UPPER LEVEL RIDGE OVER THE CARIBBEAN EXTENDS NE INTO THE W-CENTRAL ATLC THROUGH PUERTO RICO AND THE VIRGIN ISLANDS. FARTHER E...AN UPPER TROUGH AND ASSOCIATED COLD FRONT N OF THE AREA CONNECTS TO A SFC TROUGH NEAR 31N33W AND EXTENDS TO 21N52W. A NARROW LINE OF LOW CLOUDS ARE ASSOCIATED WITH THIS BOUNDARY. AN UPPER RIDGE DOMINATES THE E ATLC ANCHORED ON A 1021 MB HIGH LOCATED NEAR 30N27W. THIN HIGH CLOUDS EXTEND FROM N SOUTH AMERICA ACROSS THE OCEAN ASSOCIATED WITH STRONG WLY WINDS. $$ RJW