000 AXNT20 KNHC 082353 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU MAR 08 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 8N12W 4N25W 2N40W TO THE COAST OF NE BRAZIL NEAR EQ50W. NO SIGNIFICANT DEEP CONVECTION IS NOTED ALONG THE ITCZ AXIS. ONLY SMALL POCKETS OF ISOLATED WEAK CONVECTION ARE NEAR 4.5N-21W...AND 3N36W. CLUSTERS OF SCATTERED MODERATE WITH EMBEDDED ISOLATED STRONG CONVECTION ARE WELL SOUTH OF THE ITCZ OVER NE BRAZIL. ...DISCUSSION... GULF OF MEXICO... FAIRLY LIGHT WINDS AND LOW SEAS CONTINUE IN THE GULF THANKS TO A WEAK SFC RIDGE THAT STRETCHES ACROSS THE AREA WITH A 1021 MB HIGH LOCATED NEAR 29N92W. BROKEN TO OVERCAST LOW TO MID CLOUDS ARE OBSERVED OVER THE YUCATAN PENINSULA/CHANNEL ASSOCIATED WITH THE REMNANT OF A WEAK SFC LOW THAT WAS OVER THE GULF OF HONDURAS YESTERDAY EVENING. IN THE UPPER LEVELS...A RIDGE DOMINATES THE ENTIRE GULF AND THE SUNSHINE STATE. SWLY FLOW ON THE W PERIPHERY OF THIS RIDGE IS SPREADING HIGH LEVEL MOISTURE FROM THE EPAC INTO CENTRAL MEXICO AND THE NORTHERN GULF WATERS N OF 23N. MODERATE DRY AIR EXISTS ELSEWHERE...BUT PARTICULARLY OVER THE BAY OF CAMPECHE. HIGH PRES ALONG N GULF COAST WILL REMAIN IN CONTROL OF THE WEATHER PATTERN ACROSS THE GULF THROUGH SUNDAY. CARIBBEAN... A WEAK SFC TROF HAS PERSISTED IN THE GULF OF HONDURAS EXTENDING INLAND OVER NRN BELIZE. THIS FEATURE IS GENERATING AN AREA OF LOW TO MID LEVEL CLOUDS WITH EMBEDDED SHOWERS WHICH COVERS THE YUCATAN PENINSULA/CHANNEL AND THE NW CARIBBEAN W OF 84W. THIS CLOUDINESS IS ALSO AFFECTING W CUBA. THE GFS MODEL SUGGESTS THE REMNANT MOISTURE WILL LINGER OVER THE YUCATAN PENINSULA AND ADJACENT AREA THE NEXT COUPLE OF DAYS. A SFC TROUGH LOCATED OVER THE CENTRAL BAHAMAS IS ENHANCING THE DEVELOPMENT OF SHOWERS AND ISOLATED TSTMS OVER E CUBA. ELSEWHERE FAIRLY TYPICAL CONDITIONS EXIST WITH MODERATE TO FRESH ELY TRADES AND THIN PATCHES OF LOW-LEVEL MOISTURE STREAMING W ACROSS THE BASIN. ALOFT...A RIDGE/TROUGH/RIDGE PATTERN DOMINATES THE REGION WITH THE TROUGH EXTENDING SWWD FROM ATLC ACROSS HISPANIOLA TO 12N80W. WSW UPPER LEVEL WINDS BETWEEN THIS TROUGH AND AN UPPER HIGH OVER N SOUTH AMERICA ARE TRANSPORTING HIGH LEVEL MOISTURE/CIRRUS CLOUDS FROM COSTA RICA/PANAMA TO N COLOMBIA/VENEZUELA. A CLIMATOLOGICAL LOW PRES OVER N COLOMBIA IS GIVING THE AREA SOME SHOWER/TSTM ACTIVITY. WESTERN ATLANTIC... MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS AND TSTMS COVER A GOOD PORTION OF THE W-CENTRAL ATLC BETWEEN THE BAHAMAS AND 53W. THIS CONVECTIVE ACTIVITY IS ASSOCIATED WITH SEVERAL FEATURES...A SFC TROUGH THAT RUNS FROM 29N73W TO 21N76W...CROSSING THE CENTRAL BAHAMAS...A WEAKENING FRONTAL BOUNDARY THAT ENTERS THE REGION NEAR 30N50W AND EXTENDS TO 26N60W...AND ANOTHER SFC TROUGH THAT GOES FROM 26N60W TO 26N69W. 10M BOUNDARY LAYER WINDS SHOW VERY WELL THE PRESENCE OF THE TROUGH OVER THE BAHAMAS AND REGIONAL COASTAL WATERS...WITH SE WINDS E OF THE TROUGH AXIS AND SLIGHTLY STRONGER NE WINDS W OF THE TROUGH AXIS. ALOFT...A SHORT WAVE TROUGH OVER THE AREA IS SUPPORTING THE DEVELOPMENT OF THIS CONVECTIVE ACTIVITY. A LOW IS EXPECTED TO DEVELOP E OF THE BAHAMAS NEAR 26N70W ON FRI. PRES GRADIENT WILL TIGHTEN BETWEEN THIS LOW AND STRONG HIGH PRES LOCATED N OF THE AREA BRINGING AN INCREASE IN WINDS AND SEAS N OF 27N W OF 55W FRI AND SAT. THE LOW WILL LIKELY CONTINUE TO PRODUCE SOME UNSETTLED WEATHER FOR PORTIONS OF THE W-CENTRAL ATLC. EASTERN ATLANTIC... A STRONG 1034 MB HIGH PRES SYSTEM LOCATED BETWEEN PORTUGAL AND THE AZORES IS DOMINATING THE SFC PATTERN ACROSS THE ATLC E OF 45W. THIS HIGH IS PRODUCING MODERATE TO STRONG TRADE WINDS ACROSS A GOOD PORTION OF THE DISCUSSION AREA PARTICULARLY E OF 30W WHERE TIGHTEST PRES GRAD EXISTS. THE ONCE VIGOROUS UPPER LOW HAS OPENED INTO A WEAKENING TROUGH ALIGNED ALONG 35W/36W N OF 15N. SWLY UPPER LEVEL FLOW AND DIFFLUENCE TO THE E OF THE TROUGH AXIS IS STILL GENERATING PATCHY MID-HIGH LEVEL MOISTURE FROM 20N TO BEYOND 32N BETWEEN 20W-30W. THIS MOISTURE PLUME IS THINNER THAN IT WAS YESTERDAY AT THIS TIME AND THIS TREND IS EXPECTED TO CONTINUE AS THE TROUGH PULLS NWD AND DISSIPATES LATER TONIGHT OR FRI. MOSTLY FAIR WEATHER WILL DOMINATE THE AREA THIS UPCOMING WEEKEND AS STRONG DEEP LAYER RIDGING BECOMES WELL ESTABLISHED OVER THE FAR E ATLC. $$ GR