000 AXNT20 KNHC 181126 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST SAT MAR 18 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N10W 4N20W 3N30W 4N40W 4N50W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS ALONG THE COAST OF W AFRICA FROM EQ-3N BETWEEN 1W-5W. ISOLATED MODERATE CONVECTION IS FROM 3N-6N BETWEEN 16W-18W... AND FROM 1N-5N BETWEEN 40W-51W. ...DISCUSSION... GULF OF MEXICO... AS OF 0900 UTC...1019 MB HIGH IS CENTERED OVER THE NE GULF OF MEXICO NEAR 28N88W. RETURN SW FLOW IS PRODUCING WIDELY SCATTERED MODERATE CONVECTION ALONG THE SLOPES OF THE SIERRA MADRE MOUNTAINS AND THE MEXICAN COAST FROM 21N-26N BETWEEN 95W-100W. SLY RETURN FLOW OVER E TEXAS AND S LOUISIANA IS PRODUCING A SLOW MOVING WARM FRONT ALONG 29N100W 30N97W 29N90W. THE TAIL END OF A COLD FRONT IS OVER N FLORIDA ALONG 30N79W 28N80W 27N84W. NO CONVECTION IS ALONG THE FRONT. SLIGHT TEMPERATURE CHANGES ARE ON EACH SIDE OF THE FRONT. IN THE UPPER LEVELS... A BROAD RIDGE IS OVER THE GULF PRODUCING MOSTLY WLY FLOW. PACIFIC MOISTURE IS OVER MEXICO AND THE CENTRAL GULF BETWEEN 22N-27N. EXPECT...THE SURFACE HIGH TO DISSIPATE OVER THE NEXT 24 HOURS HOWEVER A SURFACE RIDGE AXIS WILL CONTINUE THE RETURN FLOW OVER THE W GULF. THE WARM FRONT WILL DRIFT FURTHER N INTO TEXAS. THE COLD FRONT OVER FLORIDA WILL MOVE DOWN TO S FLORIDA WITH NO CONVECTION AND LITTLE TEMPERATURE CHANGE. CARIBBEAN SEA... SCATTERED SHOWERS REMAIN OVER N COLOMBIA AS THUNDERSTORMS DISSIPATE. 15-20 KT TRADES ARE OVER THE CARIBBEAN SEA. PATCHES OF BROKEN LOW CLOUDS AND SCATTERED SHOWERS ARE OVER PORTIONS OF THE LEEWARD ISLANDS TO INCLUDE PUERTO RICO AND HISPANIOLA. IN THE UPPER LEVELS...A SMALL TROUGH IS OVER THE W CARIBBEAN W OF 75W. A RIDGE IS OVER THE REMAINDER OF THE SEA PRODUCING SW FLOW. A GOOD AMOUNT OF UPPER LEVEL MOISTURE IS OVER COLOMBIA WHILE STRONG SUBSIDENCE IS OVER THE CARIBBEAN SEA. EXPECT...THE UPPER AIR PATTERN TO SHIFT E OVER THE NEXT 24 HOURS WITH NO CHANGE IN THE SURFACE TRADES. THE BEST CHANCE OF SHOWERS WILL BE OVER THE WINDWARD AND LEEWARD ISLANDS. ATLANTIC OCEAN... A 1013 MB LOW IS OFF THE COAST OF SOUTH CAROLINA NEAR 31N78W. COLD FRONT EXTENDS SW TO FLORIDA NEAR 28N80W. A SMALL WARM FRONT EXTENDS E FROM THE LOW TO 31N74W. ANOTHER 1009 MB LOW IS FURTHER E NEAR 33N69W. A COLD FRONT EXTENDS SW FROM THIS LOW TO 31N74W. ISOLATED SHOWERS ARE ALONG THE FRONTAL SYSTEMS TO THE FLORIDA COAST. A SURFACE TROUGH EXTENDS FROM 30N69W TO THE BAHAMAS NEAR 26N77W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. A WEAK STATIONARY FRONT IS ALONG 32N36W 28N54W. BROKEN LOW CLOUDS AND SCATTERED SHOWERS ARE WITHIN 90 NM OF THE FRONT. A 1020 MB HIGH IS FURTHER SE AT 25N43W. A 995 MB LOW W OF PORTUGAL EXTENDS A SURFACE TROUGH TO NEAR THE CANARY ISLANDS. AN AREA OF AFRICAN DUST CONTINUES TO SLOWLY THIN OVER THE TROPICAL ATLANTIC FROM THE ITCZ NORTHWARD TO 20N E OF 52W. IT DOES NOT APPEAR THAT THE DUST IS RESTRICTING SURFACE VISIBILITIES ACROSS THE TROPICAL ATLANTIC OR EAST CARIBBEAN. IN THE UPPER LEVELS...MOSTLY WESTERLY ZONAL FLOW IS OVER THE ATLANTIC N OF 20N. AN ANTICYCLONIC CIRCULATION IS CENTERED OVER THE TROPICS NEAR 5N40W. BROAD ANTICYCLONIC FLOW IS FROM EQ-20N BETWEEN 20W-75W. EXPECT THE STATIONARY FRONT TO CONTINUE TO WEAKEN AND DISSIPATE WITHIN THE NEXT 12-18 HOURS DUE TO LACK OF UPPER AIR SUPPORT. $$ FORMOSA