000 AXNT20 KNHC 202305 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST MON MAR 20 2006 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...WEATHER OBSERVATIONS... RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2300 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N11W 3N20W 2N30W TO THE EQ39W. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION IS LOCATED WITHIN 120 NM...MOSTLY TO THE NORTH OF THE AXIS. A NEWLY FORMED CLUSTER OF CONVECTION HAS FIRED FROM 2N-5N BETWEEN 9W-12W. ...DISCUSSION... GULF OF MEXICO... A STRONG MID-UPPER LEVEL RIDGE WHICH HAS BEEN CENTERED OVER THE GULF OVER THE PAST COUPLE OF DAYS HAS SHIFTED SLIGHTLY TO THE EAST WITH THE UPPER AXIS ALONG 85W/86W. A PRONOUNCED SUB-TROPICAL SOUTHWESTERLY JET WITH UPPER WINDS NEAR 90-100 KT IS RIDING OVER THE TOP OF THE RIDGE TRANSPORTING CONSIDERABLE MOISTURE FROM THE EPAC ACROSS MEXICO AND INTO THE SE U.S. MODERATE TO STRONG SUBSIDENCE IS HOLDING ON OVER THE EASTERN GULF AND FLORIDA BUT WILL SOON BE REPLACED BY MID-UPPER LEVEL CLOUDINESS. A COLD FRONT HAS ENTERED THE NW GULF THIS MORNING AND AS OF 2100 UTC...EXTENDS FROM NEAR HOUSTON TO THE TX/MX BORDER ALONG 30N85W 26N97W TO INLAND OVER MEXICO. MULTILAYER CLOUDS AND SCATTERED SHOWERS SPREAD 125 NM AHEAD OF THE BOUNDARY. HEAVY RAINFALL AND SEVERE WEATHER IS OCCURRING INLAND OVER THE SE U.S MOVING NEWARD. S/SSE SURFACE FLOW FROM 15-20 KT AND VERY MILD WEATHER DOMINATES THE BASIN. THE COLD FRONT WILL CONTINUE TO PROGRESS SEWARD AND WILL BE POSITIONED FROM CENTRAL FLORIDA TO S MEXICO NEAR 21N97W IN 24 HOURS. COOLER AND DRIER CONDITIONS DRIVEN BY NORTHERLY WINDS WILL BE USHERED IN BEHIND THE FRONT. CARIBBEAN... A STRONG MID-UPPER LEVEL ANTICYCLONE IS CENTERED NEAR THE CAYMAN ISLANDS WHILE MAINLY ZONAL WESTERLIES COVER MUCH OF THE BASIN. DRY AIR ALOFT IS WIDESPREAD ACROSS THE AREA ESPECIALLY W OF 75W. STRONG SUBSIDENCE HAS ONLY ALLOWED SMALL PATCHES OF SCATTERED LOW CLOUDS TO FORM ACROSS THE SEA. SCATTERED SHOWERS ARE OVER PUERTO RICO AND HISPANIOLA ASSOCIATED WITH A W ATLANTIC COLD FRONT AND ENHANCED BY THE LOCAL OROGRAPHY. MODERATE EASTERLY TRADES FROM 15-25 KT ARE BLOWING E OF 80W WITH SE WINDS NEAR 15-25 KT W OF 80W. SIMILAR WEATHER CONDITIONS ARE EXPECTED TOMORROW AND MODERATE TRADE WINDS WILL PERSIST ACROSS THE BASIN THROUGH THURSDAY. ATLANTIC... A MID-UPPER RIDGE EXTENDS FROM THE GULF OF MEXICO TO THE W ATLANTIC W OF 75W. A BROAD 981 MB LOW OVER NEWFOUNDLAND IS PRODUCING UPPER LEVEL WESTERLIES AS FAR SOUTH AS THE BAHAMAS AND GREATER ANTILLES. THIS LOW HAS ALSO ENHANCED A STRONG 120-150 KT NW/WNW JET N OF 30N W OF 40W. A SERIES OF LOWS AND FRONTS HAVE DEVELOPED SEWARD OF THE BROAD LOW. TWO COLD FRONTS HAVE ENTERED THE DISCUSSION AREA. THE WESTERN-MOST FRONT IS LOCATED ALONG 32N47W 26N57W 23N70W. A BROKEN LINE OF MULTILAYER CLOUDS AND SCATTERED SHOWERS SPREAD ABOUT 75 NM AHEAD OF THE FRONT. THE OTHER COLD FRONT IS LOCATED ABOUT 300 NM TO THE EAST ALONG 32N39W 26N47W 22N56W. A SIMILAR LINE OF CLOUDS AND SHOWERS ARE ASSOCIATED WITH THIS BOUNDARY. COLD AIR STRATOCUMULUS CLOUDS ARE BUILDING IN BEHIND THE SECOND BOUNDARY. FARTHER EAST...A MID-UPPER LEVEL RIDGE EXTENDS FROM 20W-40W N OF 20N. AT THE SFC...A 1020 MB HIGH IS LOCATED NEAR 28N30W. GENERALLY FAIR WEATHER LIES UNDER THE INFLUENCE OF THE RIDGE. AN UPPER LEVEL TROUGH COVERS THE REMAINDER OF THE ATLANTIC. A SUB-TROPICAL JET WITH UPPER LEVEL WINDS FROM 100-120 KT LIES INLAND OVER AFRICA. $$ CANGIALOSI