000 AXNT20 KNHC 311042 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT MAR 31 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 8N12W 3N20W 2N30W 1N40W 1S50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS AFFECTING WRN AFRICA AND ADJACENT ATLC WATERS FROM 3S-11N BETWEEN 2W-12W. SCATTERED MODERATE IS ALSO WITHIN 120NM N OF THE AXIS BETWEEN 14W-34W. ISOLATED MODERATE IS WITHIN 90NM OF AXIS BETWEEN 39W-47W. ...DISCUSSION... THE GULF OF MEXICO... A 1026 MB SFC HIGH PRES NEAR OCRACOKE NC CONTINUES TO EXTEND SW OVER THE GULF THIS MORNING. THIS IS PRODUCING ABUNDANT 15-20 KT E TO SE WINDS ACROSS THE BASIN WHICH IN TURN ARE GENERATING MODERATE WIND WAVES AND SWELL...MOSTLY IN THE 4-6' RANGE EXCEPT LARGER IN THE STRAITS OF FLORIDA. THE RIDGING ACROSS THE GULF WILL WEAKEN THROUGH TONIGHT IN ADVANCE OF A WEAK COLD FRONT TO PUSH OFF THE TEXAS COAST LATER THIS EVENING. DEEP CONVECTION REMAINS AT A MINIMUM OVER THE GULF THOUGH STRONG TSTMS CURRENTLY OVER ERN TX WITH THE APPROACHING FRONT MAY AFFECT THE NW GULF LATER TODAY. KEY WEST RADAR DATA SHOWS ISOLD SHOWERS PUSHING THROUGH THE STRAITS OF FLORIDA...LIKELY BEING ENHANCED BY THE TAIL END OF A BACKDOOR COLD FRONT FROM THE ATLC. RIDGING CONTINUES TO DOMINATE THE UPPER LEVELS OVER THE GULF IN ADVANCE OF THE DEEP LAYER TROUGHING MOVING E OF THE ROCKIES. DRY/STABLE MID TO UPPER AIR ALSO DOMINATES THE BASIN ASIDE FROM BROKEN CIRRUS OVER THE FAR NW AND SW PORTIONS. THE CARIBBEAN SEA... MODERATE TO FRESH NE SFC WINDS DOMINATE MUCH OF THE CARIB THIS MORNING...THOUGH STRONGER WINDS ARE BEING FELT IN THE ATLC PASSAGES AS STRONG REINFORCING HIGH PRESSURE CENTERED NEAR THE OUTER BANKS OF NC BUILDS IN. AN EARLIER QUIKSCAT PASS SHOWED A BAND OF 25-30 KT NE WINDS IN THE WINDWARD PASSAGE BETWEEN JAMAICA AND THE TURKS AND CAICOS. HIGHER SEAS SHOULD ALSO BE ANTICIPATED IN THESE EXPOSED ATLC PASSAGES...SEE OFFSHORE WATERS FORECAST UNDER MIAOFFNT3 FOR MORE DETAILS. A WEAK FRONTAL BOUNDARY AT THE LEADING EDGE OF THE HIGH WILL PUSH INTO THE NE CARIB LATER TODAY. A BAND OF PREFRONTAL LOW CLOUDS/POSSIBLE SHOWERS HAVE DEVELOPED BETWEEN NRN NICARAGUA AND HAITI OVER THE LAST FEW HOURS. ALOFT...A BROAD UPPER RIDGE CONTINUES TO DOMINATE FROM ITS ORIGIN OVER THE TROPICAL ATLC. THIS IS ADVECTING HIGH CLOUDS INTO THE CARIB ESPECIALLY S OF 16N E OF 75W. DEEP LAYER TROUGH DOMINATING THE WRN ATLC IS MOSTLY N OF THE AREA. THE ATLANTIC OCEAN... SFC HIGH PRESSURE IS BUILDING INTO THE WRN ATLC BEHIND A BACKDOOR FRONT THAT ENTERS THE AREA NEAR 32N48W AND CONTINUES SW TO NEAR 21N73W. A NEWLY FORMED 1006 MB LOW IS ALONG THE FRONT NEAR 29N53W WHICH IS A REFLECTION OF THE MID TO UPPER LOW JUST TO ITS W. MODERATE TO STRONG NLY WINDS BEHIND THE FRONT ARE ADVECTING INCREASING STRATOCUMULUS CLOUDS INTO THE AREA N OF 22N BETWEEN 60W-78W. THE FRONT IS ASSOCIATED WITH DEEP LAYER TROUGHING DOMINATING THE WRN ATLC. SCATTERED MODERATE CONVECTION WITH POSSIBLE TSTMS ARE IN THE UPPER DIFFLUENT ZONE AHEAD OF THE TROUGHING...N OF 26N BETWEEN 48W-54W. A REMNANT SFC TROUGH REMAINS AHEAD OF THE COLD FRONT IN THE CENTRAL ATLC WATERS...ALONG 32N44W 20N52W TO THE WINDWARD ISLANDS NEAR 13N61W. SCATTERED SHOWERS WITH POSSIBLE EMBEDDED TSTMS ARE WITHIN 250 NM MAINLY E OF THIS TROUGH...ESPECIALLY N OF 20N. A 1004 MB LOW IS ATTACHED TO THE TROUGH NEAR 28N46W...WHICH IS EXPECTED TO MOVE NE OF THE AREA DURING SAT. MUCH OF THE REMAINDER OF THE E ATLC IS DOMINATED BY RIDGING AT ALL LEVELS. A 1028 MB SFC HIGH IS BETWEEN THE AZORES AND MADEIRA ISLAND...WHICH IS PRODUCING ABUNDANT FAIR WEATHER AND MODERATE TO STRONG TRADES ACROSS MUCH OF THE AREA E OF 35W. $$ WILLIS