000 AXNT20 KNHC 081801 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N13W 4N25W 2N40W TO THE COAST OF NE BRAZIL NEAR EQ50W. SCATTERED CLUSTERS OF MODERATE CONVECTION ARE FROM 2S-2N BETWEEN 27W-35W...WITHIN 30 NM OF THE AXIS BETWEEN 37W-40W...AND WITHIN 60 NM OF THE NE BRAZIL COAST FROM 3S-3N. ...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. PATCHES OF LOW TO MID CLOUDS ARE SEEN N OF THE YUCATAN FROM 21N-28N BETWEEN 85W-90W...AND ALSO JUST OFFSHORE MEXICO/S TX S OF 27N. IN THE UPPER LEVELS...THE FLOW IS MAINLY FROM THE WNW BENDING AROUND AN UPPER RIDGE THAT EXTENDS NWD FROM THE TROPICAL EPAC INTO THE WRN BAY OF CAMPECHE. SWLY FLOW ON THE W PERIPHERY OF THIS RIDGE IS SPREADING HIGH LEVEL MOISTURE FROM THE EPAC INTO CENTRAL MEXICO AND THROUGH THE GULF WATERS W OF 84W N OF 22N. MODESTLY DRY AIR EXISTS ELSEWHERE AIDING IN THE OVERALL GOOD WEATHER ACROSS THE BASIN. OVER THE NEXT COUPLE OF DAYS...LITTLE PATTERN CHANGE IS ANTICIPATED BOTH AT THE SFC AND ALOFT KEEPING WINDS LIGHT AND THE WEATHER CONDITIONS MAINLY FAIR ACROSS MOST OF THE AREA. CARIBBEAN... A WEAK SFC TROF HAS PERSISTED IN THE GULF OF HONDURAS EXTENDING INLAND OVER NRN BELIZE. THE MAIN EFFECT OF THIS WEAK SYSTEM IS AN AREA OF LOW TO MID LEVEL CLOUDS WITH EMBEDDED SHOWERS WHICH LIE ACROSS NRN CENTRAL AMERICA AND THE COASTAL WATERS FROM 15N-22N W OF 84W. ELSEWHERE FAIRLY TYPICAL CONDITIONS EXIST WITH MODERATE TO FRESH ELY TRADES AND THIN PATCHES OF LOW-LEVEL MOISTURE STREAMING W ACROSS THE SEA. ALOFT...THERE IS SLIGHT TROUGHING EXTENDING SWWD FROM ATLC ACROSS HISPANIOLA TO 12N80W. THIS TROUGH IS ENHANCING THE WIDESPREAD DRY STABLE AIR PREVENTING THE MOISTURE PATCHES FROM ACQUIRING MUCH VERTICAL DEPTH. THE WEAK SFC TROUGH IN THE NW PORTION WILL CONTINUE DRIFTING SLOWLY W WHILE WEAKENING. HOWEVER...GFS SUGGESTS THE REMNANT MOISTURE WILL LINGER OVER THE YUCATAN PENINSULA AND ADJACENT AREA THE NEXT COUPLE OF DAYS AS MOIST ONSHORE FLOW PERSISTS. ELSEWHERE...SIMILAR TRADEWIND WEATHER WILL PERSIST. WESTERN ATLANTIC... SLIGHT MID TO UPPER LEVEL TROUGHING COVERS THE MAJORITY OF THE ATLC W OF 55W EXTENDING SWD FROM A LARGE STRONG POLAR LOW. AN ASSOCIATED WEAKENING FRONTAL BOUNDARY IS LINGERING IN THE REGION ANALYZED STATIONARY ALONG 32N45W 25N58W THEN DISSIPATING TO 26N66W. BROKEN TO OVERCAST LOW AND MID LEVEL CLOUDS WITH EMBEDDED ISOLATED SHOWERS ARE WITHIN 180 NM BEHIND THE FRONT...WITH AN EMBEDDED AREA OF MODERATE CONVECTION WITH POSSIBLE TSTMS FROM 25N-28N BETWEEN 64W-69W. A SFC TROUGH REMAINS DRAPED THROUGH THE BAHAMAS AND ADJACENT ATLC WATERS ALONG 30N75W 25N76W 21N74W. THIS MORNINGS QUIKSCAT DEPICTED THIS BOUNDARY WELL. ASSOCIATED SCATTERED MODERATE CONVECTION IS FROM 22N-27N BETWEEN 72W-76W. THIS TROUGH IS LIKELY A RESULT OF ENERGY THAT BROKE OFF FROM THE WEAKENING FRONT TO THE E AND ENHANCED BY AN UPPER SHORTWAVE. LOOKING AHEAD A COUPLE OF DAYS...MAIN FOCUS WILL BE THE SFC TROUGH IN THE BAHAMAS WHICH IS EXPECTED TO DRIFT SLOWLY E TO NE. THIS WILL LIKELY CONTINUE TO PRODUCE SOME UNSETTLED WEATHER FOR PORTIONS OF THE W ATLC...ALONG WITH A POTENTIAL PROLONGED ELY SWELL EVENT FOR THE SE U.S. COAST AS THE TROUGH INTERACTS WITH HI PRES TO ITS NORTH. EASTERN ATLANTIC... A STRONG 1035 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 33W 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 16N TO BEYOND 32N BETWEEN 20W-34W. THIS MOISTURE PLUME IS SUBSTANTIALLY THINNER THAN IT WAS YESTERDAY AT THIS TIME AND THIS TREND IS EXPECTED TO CONTINUE AS THE TROUGH PULLS NWD AND DISSIPATES LATER TODAY OR FRI. FAIR WEATHER LOOKS TO BE THE THEME FOR MOST OF THE REGION THIS WEEKEND AS STRONG DEEP LAYER RIDGING BECOMES WELL ESTABLISHED. $$ WILLIS