000 AXNT20 KNHC 290600 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN OCT 29 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 47W S OF 15N MOVING W 10 TO 15 KT. THIS WAVE REMAINS RATHER LOW AMPLITUDE WITH LITTLE CURVATURE NOTED IN SATELLITE IMAGERY. WINDS AT BUOY 41041 HAVE SHOWN SOME SLIGHT VEERING OVER THE LAST FEW HOURS WHICH MAY BE ASSOCIATED WITH THE WAVE PASSAGE...THOUGH ITS STILL NOT CLEAR CUT. DEEP CONVECTION IS MINIMAL WITH A FEW SHOWERS/TSTMS NOTED FROM 10N-12N WITHIN 150NM OF EITHER SIDE OF THE AXIS. TROPICAL WAVE IS MOVING QUICKLY THROUGH THE EAST TO CENTRAL CARIBBEAN ALONG 67W MOVING W NEAR 20 KT. THIS WAVE REMAINS WELL DEFINED WITH CLEAR CYCLONIC CURVATURE NOTED IN THE LOW TO MID CLOUD FIELD...BETWEEN THE MONA PASSAGE AND THE ABC ISLANDS. SCATTERED MODERATE CONVECTION IS FROM 14N-19N BETWEEN 66W-71W. THESE SHOWERS/TSTMS HAVE CHANGED LITTLE THIS EVENING. HOWEVER...SOME SLOW DEVELOPMENT IS STILL POSSIBLE OVER THE NEXT COUPLE OF DAYS. A TROPICAL WAVE IS ALONG 78W S OF 18N MOVING W 10 TO 15 KT. THIS WAVE HAS BECOME DIFFICULT TO LOCATE OVER THE PAST SEVERAL HOURS AND IS NEARING THE COLD FRONT THAT RECENTLY ENTERED THE NW CARIBBEAN. ISOLATED MODERATE CONVECTION SEEN FROM 15N-18N BETWEEN 75W-81W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION OVER CENTRAL AMERICA AND THE ADJACENT WATERS SEEM MORE ASSOCIATED WITH THE ITCZ. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 10N14W 9N46W 9N50W TO THE SOUTH AMERICAN COAST NEAR 9N61W. SEVERAL CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION SEEN WITHIN 200NM OF EITHER SIDE OF THE AXIS BETWEEN 15W-45W...WHICH MAKES IT MORE ACTIVE THAN IT HAS BEEN OVER THE PAST FEW NIGHTS. SIMILAR CLUSTERS SEEN OFF THE NE SOUTH AMERICA COAST FROM 7N-12N BETWEEN 55W-61W. ...DISCUSSION... THE GULF OF MEXICO... SURFACE HIGH PRESSURE FROM MEXICO AND SRN TEXAS HAS SUCCESSFULLY BUILT INTO THE GULF BEHIND OUR RECENT COLD FRONT PASSAGE...PRODUCING 10-20 KT NW/N FLOW ACROSS THE AREA. THE NRN GULF IS EXPERIENCING CLEAR SKIES WITH OFFSHORE FLOW...WHILE SCATTERED TO BROKEN COOL AIR STRATOCUMULOUS CLOUDS REMAIN VISIBLE S OF 27N. ZONAL FLOW ALOFT CONTINUES TO ADVECT VERY DRY MID TO UPPER AIR E ACROSS THE GULF IN WAKE OF THE FRONTAL SYSTEM. THE POSTFRONTAL WINDS AND SEAS WILL GRADUALLY RELAX THROUGH 24HRS AND GAIN MORE OF AN EASTERLY COMPONENT AS HIGH PRESSURE DEVELOPS OVER THE CENTRAL GULF COAST. THE CARIBBEAN SEA... OUR COLD FRONT CONTINUES TO DOMINATE THE WEATHER OVER THE NW CARIBBEAN WITH THE 0300 UTC PLACEMENT BETWEEN CENTRAL CUBA AND THE COAST OF GUATEMALA. AN ASSOCIATED CLUSTER OF MODERATE CONVECTION IS HOVERING OVER THE GULF OF HONDURAS. THIS IS ALSO BEING SUPPORTED BY UPPER DIFFLUENT AIR...BETWEEN THE PRONOUNCED UPPER TROUGHING EXTENDING S FROM THE EAST COAST AND UPPER RIDGING EXTENDING THROUGH HONDURAS FROM ITS CENTER JUST OFFSHORE LIMON COSTA RICA. A SMALL UPPER TROUGH IS ALSO ALIGNED FROM SE TO NW THROUGH THE NW CARIBBEAN...THAT HAS ISOLATED SHOWERS/TSTMS ON THE PVA SIDE OF THE AXIS JUST S OF CUBA AND THE WATERS NEAR JAMAICA. AN UPPER HIGH IS NEAR THE TURKS AND CAICOS ISLANDS THAT IS AFFECTING THE NRN CARIBBEAN. UPPER DIFFLUENCE BETWEEN THIS FEATURE AND AN UPPER LOW JUST S OF THE ABC ISLANDS IS HELPING TO SUPPORT THE CONVECTION NEAR THE TROPICAL WAVE ALONG 67W. THE SHOWERS AND TSTMS ASSOCIATED WITH THIS WAVE WILL MOVE ACROSS THE CENTRAL CARIBBEAN THROUGH MONDAY WHILE THE FRONT OVER THE NW PORTION STALLS AND GRADUALLY BECOMES DIFUSE. THE ATLANTIC OCEAN... AS OF 29/0300 UTC A COLD FRONT IS OVER THE W ATLC EXTENDING THROUGH CUBA AND THE BAHAMAS TO NEAR 32N75W. ISOLATED SHOWERS/TSTMS ARE GENERALLY WITHIN 300 NM MAINLY E OF THE FRONT THOUGH THE CONVECTION IS MUCH LESS PRONOUNCED THAN IT WAS 24 HOURS AGO. THE INTERACTION BETWEEN THIS FRONTAL SYSTEM AND A 1025 MB HIGH NEAR 36N51W IS PRODUCING GALE FORCE WINDS OVER THE W ATLANTIC N OF 28N WITHIN 400 NM E OF FRONT. THE FRONT IS ASSOCIATED WITH UPPER TROUGHING EXTENDING S THROUGH THE EAST COAST...THAT IS ADVECTING VERY DRY MID TO UPPER AIR OFF THE CAROLINAS THROUGH FLORIDA. A WELL DEFINED UPPER HIGH IS ABOUT 400NM NE OF THE LEEWARD ISLANDS NEAR 24N59W...THAT HAS ABUNDANT DRY AIR ROTATING AROUND IT. E OF THIS UPPER HIGH LIES AN UPPER TROUGH THAT HAS ITS OLD ASSOCIATED FRONTAL BOUNDARY ALONG 32N34W 27N40W 24N55W. THERE IS STILL A LINE OF LOW CLOUDS ASSOCIATED WITH THIS OLD BOUNDARY...BUT THE DRY STABLE ENVIRONMENT SURROUNDING IT IS PREVENTING DEEP CONVECTION. MUCH OF THE E ATLC N OF 15N BETWEEN AFRICA AND 40W ALSO IN A DRY/STABLE ENVIRONMENT WITH SCATTERED STRATOCUMULUS CLOUDS. A BROAD UPPER LOW IS SPINNING JUST N OF THE CANARY ISLANDS AND IS SUPPORTING ISOLATED SHOWERS IN THE VICINITY. $$ WILLIS