000 AXNT20 KNHC 261759 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON MAR 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N11W 3N20W EQ30W AND INTO NE BRAZIL NEAR 1S49W. SCATTERED CLUSTERS OF MODERATE TO STRONG CONVECTION ARE OVER AFRICA AND ADJACENT ATLC WATERS FROM 2S-10N BETWEEN 10E-10W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 210 NM EITHER SIDE OF AXIS BETWEEN 24W-43W. ...DISCUSSION... GULF OF MEXICO... SFC HIGH PRESSURE JUST OFF THE MID ATLANTIC COAST CONTINUES TO EXTEND SW OVER THE GULF AND IS THE DRIVING FORCE IN TODAYS MARINE WEATHER. THE HIGH IS PRODUCING ABUNDANT MODERATE TO FRESH (11-21 KT ON THE BEAUFORT SCALE) E TO SE WINDS ACROSS THE BASIN. THESE WINDS HAVE LEVELED OFF THE SEAS IN THE 3-6 FT RANGE. WAVE SPECTRA ACROSS THE GULF ARE GENERALLY DOMINATED BY STEEP WIND WAVES WITH PEAK PERIODS MOSTLY IN THE IN THE 5-8 SEC BAND. LARGER AND STEEPER WAVES SHOULD BE ANTICIPATED IN THE STRAITS OF FLORIDA WITH THE ELY FLOW AGAINST THE OPPOSING GULF STREAM. VERY LITTLE SHOWER OR TSTM ACTIVITY NOTED ACROSS THE GULF THIS AFTERNOON...EXCEPT FOR ISOLATED CELLS IN THE STRAITS OF FLORIDA AND JUST NORTH OF THE YUCATAN CHANNEL. MORE ACTIVITY IS NOTED OVER CENTRAL TX ASSOCIATED WITH A MID TO UPPER LOW MOVING INTO SW TX NEAR 30N105W. UPPER DIFFLUENCE BETWEEN THE TROUGH AND THE DOMINATING UPPER RIDGE OVER THE GULF IS SUPPORTING THE SHOWER/TSTM ACTIVITY OVER TX. ASSOCIATED UPPER MOISTURE IS SPREADING INTO MAINLY THE NW GULF. SFC RIDGING WILL KEEP SIMILAR CONDITIONS ACROSS THE GULF THROUGH MIDWEEK. THE MID TO UPPER TROUGH WILL MOVE THROUGH TX AND INTO OK THROUGH TOMORROW. MOST OF THE ASSOCIATED SHOWER/TSTM ACTIVITY IS EXPECTED TO STAY INLAND THOUGH SOME MAY SPILL INTO THE FAR NW GULF. CARIBBEAN... MOST ACTIVE WEATHER IN THE CARIBBEAN CONTINUES TO BE AHEAD OF THE SHARP MID TO UPPER TROUGHING EXTENDING S THROUGH THE WINDWARD PASSAGE TO NEAR PANAMA. ASSOCIATED BROKEN TO OVERCAST MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS ARE FROM 13N-24N BETWEEN 65W-76W...WHICH ARE AFFECTING PUERTO RICO...HISPANIOLA..AND THE TURKS AND CAICOS. LIGHTNING DATA HAVE CONTINUED TO DEPICT ISOLATED TO SCATTERED TSTMS IN THIS VICINITY AS WELL. THE UPPER TROUGH HAS A SFC REFLECTION AS A TROUGH FROM THE ATLC ALONG 20N68W 14N71W. GFS SUGGESTS THIS AREA OF UNSETTLED WEATHER WILL MOVE LITTLE THROUGH MIDWEEK...SO MARINE INTERESTS NEAR HISPANIOLA SHOULD ANTICIPATE SHOWER ACTIVITY WITH EMBEDDED TSTMS TO PERSIST OVER THE NEXT DAY OR SO. THE REMAINDER OF THE E CARIB E OF 65W IS UNDER A THICK CIRRUS SHIELD IN THE UPPER DIFFLUENT ZONE AHEAD OF THE UPPER TROUGH. UNDER THE SHIELD WOULD EXPECTED SCATTERED LOW CLOUDS WITH ISOLATED SHOWERS IN MOIST 5-15 KT E/SE FLOW. A BIT STRONGER NE WINDS ARE BEING FELT IN THE NW CARIB/SW OF CUBA WHERE A TIGHTER GRADIENT EXISTS BETWEEN THE TROUGHING AND THE HIGH OFF THE MID ATLC U.S. COAST. ATLANTIC... THE INTERACTION BETWEEN HIGH PRESSURE OFF THE MID ATLC COAST AND A SFC TROUGH IN THE W/CNTRL ATLC BETWEEN HAITI AND 29N55W IS PRODUCING A LARGE SWATH OF MODERATE TO STRONG NE WINDS AND WIND WAVES IN THE WRN ATLC. A REINFORCING COLD FRONT EXTENDING WSW INTO THE REGION ALONG 32N53W 28N70W HAS EXPANDED THIS REGION OF HIGH NE WINDS...NOW OVER MUCH OF THE AREA W OF 55W. SCATTERED TO BROKEN MOSTLY LOW TO MID CLOUDS WITH EMBEDDED SHOWERS ARE ASSOCIATED WITH THE SFC TROUGHING ESPECIALLY N OF 22N BETWEEN 45W-55W. MORE CONCENTRATED SHOWER/TSTM ACTIVITY AHEAD OF AN UPPER TROUGH IS AFFECTING THE CARIBBEAN REGION AND ADJACENT SW N ATLC WATERS AS DESCRIBED ABOVE. THE REMAINDER OF THE E AND CENTRAL ATLC SFC PATTERN IS DOMINATED BY A 1030 MB HIGH S OF THE AZORES NEAR 35N32W. THIS IS PRODUCING WIDESPREAD 15-25 KT TRADES AND FAIR WEATHER E OF 55W. UPPER FLOW IS HIGHLY ZONAL OVER THIS PORTION OF THE ATLC AS WELL...N OF AN UPPER ANTICYCLONE NEAR 6N44W. THE STRONG NE WINDS NE OF THE BAHAMAS AND HISPANIOLA WILL PERSIST INTO TUE AND THEN SLOWLY RELAX THROUGH THE SECOND PART OF THE WEEK AS HIGH PRES OFF THE MID ATLC COAST MOVES S AND WEAKENS. HI PRES WILL MOVE SLOWLY BETWEEN THE AZORES AND PORTUGAL KEEPING MODERATE TO FRESH TRADES OVER THE E ATLC. CONFLUENCE BETWEEN THE TWO HIGHS WILL CONTINUE TO SUPPORT TROUGHING/SHOWERS IN THE CENTRAL ATLC. $$ WILLIS