000 AXNT20 KNHC 020003 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU MAR 01 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 2345 UTC. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N9W 1N20W EQ35W AND INTO NE BRAZIL NEAR 2S47W. ISOLATED CLUSTERS OF MODERATE CONVECTION ARE WITHIN 210 NM N AND 150 NM S OF THE AXIS W OF 13W. THE MOST SIGNIFICANT OF THESE CLUSTERS IS NEAR 5N18W...OR ABOUT 375NM W OF THE AFRICAN COAST. ...DISCUSSION... THE GULF OF MEXICO... A COLD FRONT HAS ENTERED THE NW GULF AND AS OF 01/2100 UTC EXTENDS FROM THE LOUISIANA COAST NEAR 30N92W SW TO JUST OFFSHORE MEXICO NEAR 23N97W. THE FRONT HAS BEEN FAIRLY EASY TO PLACE WITH NW TO N WINDS 10-20 KT AND DEWPOINTS DROPPING INTO THE 50S BEHIND THE FRONT...AND SLY WINDS GENERALLY 15-25 KT AND DEWPOINTS IN THE 70S AHEAD OF THE FRONT. WIDESPREAD SEVERE WEATHER OUTBREAK AHEAD OF THE FRONT IS STILL AFFECTING MUCH OF THE SE U.S. A FEW CELLS ARE MOVING NE THROUGH THE FAR NRN GULF...N OF 28N BETWEEN 86W-91W. VERY STRONG CLUSTER OF STORMS SKIRTED THE GULF WATERS BETWEEN NEW ORLEANS AND MOBILE BETWEEN 20-22 UTC...WITH THE SLIDELL RADAR SHOWING SEVERAL THREE BODY SCATTER SPIKES...THE CLASSIC SIGNAL OF LARGE HAIL. THE FRONT IS ASSOCIATED WITH THE DEEP LAYER LOW SPINNING OVER IOWA. PRESENTLY THOUGH...UPPER RIDGING EXTENDING INTO THE GULF FROM THE NE PAC HAS WNW/NW FLOW OVER THE GOMEX. THIS IS ADVECTING A BAND OF UPPER MOISTURE THROUGH THE GULF MAINLY N OF 23N. FRONT EXPECTED TO MOVE TO A PSN BETWEEN NORTH CENTRAL FLORIDA AND THE BAY OF CAMPECHE BY FRI NIGHT. SCATTERED SHOWERS AND TSTMS WILL MOVE E WITH THE FRONT...MAINLY N OF 25N. THE CARIBBEAN SEA... THE MAIN STORY IN THE CARIBBEAN CONTINUES TO BE THE BRISK ELY TRADES OVER MUCH OF THE AREA E OF 82W...AS SFC HIGH PRES N OF THE AREA INTERACTS WITH LOWER PRESSURE NEAR COLOMBIA. THE TRADE FLOW CONTINUES TO BE STRONGEST NEAR THE COLOMBIAN COAST WHERE NEAR GALE CONDITIONS EXPECTED THROUGH FRI. THIS WILL ALSO CONTINUE TO SEND MODERATE TO STRONG SURF TO THE CARIB COAST OF NICARAGUA...COSTA RICA...AND PANAMA OVER THE NEXT FEW DAYS. SFC WINDS BEND MORE SLY IN THE NW CARIB IN ADVANCE OF THE FRONTAL SYSTEM MOVING INTO THE GULF. THE TRADES ARE ADVECTING TYPICAL PATCHES OF LOW LEVEL MOISTURE WWD. HOWEVER...VERY LITTLE CLOUD COVER IS SEEN OVER CARIB WATERS NEAR THE COLOMBIAN COAST WHERE THE TRADES ARE STRONGEST...WHICH HAS LED TO A WELL MIXED LOWER ATMOSPHERE. ALOFT...VERY DRY AND STABLE AIR DOMINATES YET AGAIN WHICH HAS BEEN THE STORY FOR MUCH OF THE WINTER. THIS DRY AIR IS ROTATING AROUND UPPER RIDGING CLIPPING THE FAR NW AND SE PORTIONS...AND THE DOMINATING MID TO UPPER TROUGH EXTENDING SW BETWEEN PUERTO RICO AND NRN COSTA RICA. THIS TROUGH HAS LED TO AN UPPER CONFLUENT ZONE OFFSHORE NICARAGUA AND COSTA RICA...WHERE THE DRIEST AIR IS SEEN. THE ATLANTIC OCEAN... FAIRLY AMPLIFIED UPPER RIDGE/TROUGH/RIDGE/TROUGH DOMINATES THE DISCUSSION AREA. THE UPPER RIDGING BUILDING INTO THE WRN ATLC IS SPREADING MOISTURE OVER THE CONVECTION IN THE SE U.S. OUT TO 70W. SHARP UPPER TROUGH AHEAD OF THIS IS ALONG 62W. UPPER DIFFLUENT ZONE AHEAD OF THIS TROUGH IS HELPING TO SUPPORT THE SCATTERED MODERATE CONVECTION SEEN FROM 25N-31N BETWEEN 55W-60W...AND ALSO N OF 28N BETWEEN 44W-51W. AT THE SFC...RIDGING GENERALLY DOMINATES THE WRN AND ERN PORTIONS WITH A 1022MB CENTER OFFSHORE HATTERAS NEAR 35N69W AND A 1026MB CENTER W OF MADEIRA ISLAND NEAR 32N23W. LOW LEVEL CONFLUENT ZONE BETWEEN THESE TWO HIGHS IS SUPPORTING THE COLD FRONT THAT ENTERS THE AREA IN THE CENTRAL ATLC NEAR 32N44W AND CONTINUES SW TO 26N58W AND THEN IS A TROUGH THROUGH THE SE BAHAMAS NEAR 23N74W. THIS FRONT WILL GRADUALLY BECOME DIFFUSE INTO THE WEEKEND...WHILE THE HIGH OFFSHORE HATTERAS SLIDES E AHEAD OF THE NEXT FRONT TO PUSH OFFSHORE INTO THE FAR NW PORTION OF THE DISCUSSION AREA DURING FRI AND SAT. $$ WILLIS