000 AXNT20 KNHC 132357 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE FEB 13 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 2315 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N AT THE PRIME MERIDIAN 4N15W 3N30W CROSSING THE EQUATOR NEAR 40W AND CONTINUING INTO NE BRAZIL NEAR 4S45W. ISOLATED MODERATE CONVECTION IS WITHIN 140 NM S OF THE AXIS E OF 10W. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ARE OVER NE BRAZIL. ...DISCUSSION... THE GULF OF MEXICO... A COLD FRONT HAS ENTERED THE NW PORTION OF THE GULF TODAY. AS OF 21Z...THIS FEATURE EXTENDS FROM SE LOUISIANA TO NE MEXICO AND IS WELL DEFINED ON VIS SATELLITE IMAGERY BY A NARROW LINE OF LOW CLOUDS OVER THE GULF OF MEXICO. MOSAIC DOPPLER RADAR INDICATES A STRONG LINE OF SHOWER/TSTMS MOVING ACROSS THE STATE OF GEORGIA TOWARD SOUTH CAROLINA AND ANOTHER BAND OF SIMILAR CONVECTION JUST AHEAD OF THE FRONT MOVING EWD ACROSS ALABAMA. A DIFFLUENT PATTERN ALOFT IS ENHANCING ALL THIS CONVECTIVE ACTIVITY. A PRONOUNCED WIND SHIFT AND DROPPING TEMPS/DEWPTS ARE ALSO ACCOMPANYING THE FRONT. NLY WINDS OF 15 TO 20 KT ARE ALREADY BLOWING ACROSS THE NW CORNER OF THE GULF AND WILL CONTINUE TO INCREASE AS HIGH PRES BUILDS SOUTH TIGHTENING THE PRES GRAD AND ADVECTING A MUCH COOLER AIRMASS. GALE CONDITIONS ARE FORECAST W OF 95W ON THU. ACCORDING TO THE GFS MODEL...THE COLD FRONT WILL CONTINUE TO MOVE SE ACROSS THE AREA TONIGHT AND WILL EXTENDS FROM CENTRAL FLORIDA TO NEAR TAMPICO MEXICO WEDNESDAY AFTERNOON. BY EARLY THURSDAY THE FRONT IS EXPECTED TO REACH SOUTH FLORIDA. A MID/UPPER LEVEL TROUGH MOVING ACROSS THE EASTERN US IS SUPPORTING THIS FRONTAL BOUNDARY. A SUBTROPICAL JETSTREAM WITH CORE WINDS OF 110 TO 130 KT CROSSES N MEXICO...SOUTH TEXAS AND THE NORTHERN GULF WATERS INTO THE FLORIDA PANHANDLE. THE CARIBBEAN SEA... A SHORTWAVE TROUGH CONTINUES TO PULL EWD WITH THE AXIS EXTENDING FROM THE CENTRAL BAHAMAS/CUBA TOWARD HONDURAS. THIS TROUGH HAS SHIFTED THE LARGE STRONG MID-UPPER LEVEL HIGH EWD AND NOW IS CENTERED JUST E OF THE ABC ISLANDS. THE STRONG SWLY FLOW AHEAD OF THIS SHORT WAVE TROUGH IS ADVECTING DEEPER MOISTURE FURTHER N ACROSS THE SW NORTH ATLC WHERE THE UPPER ENERGY IS STRONGER. ABUNDANT MID/UPPER DRY SINKING AIR CONTINUES TO DOMINATE THE BASIN...SUPPRESSING ANY SIGNIFICANT SHOWER/TSTM ACTIVITY FROM FORMING. PATCHES OF LOW LEVEL MOISTURE ARE MOVING ACROSS THE TROPICAL NORTH ATLC AND THE E CARIBBEAN. EARLIER QSCAT PASS SHOWED ELY TRADE WINDS OF 20 TO 30 KT WITH THE STRONGEST WINDS JUST OF THE COLOMBIAN COAST. WINDS WILL RELAX AND VEER MORE TO THE SOUTH IN RESPONSE TO A DEEPENING LOW PRES SYSTEM OVER THE SRN U.S. THE COLD FRONT...THAT IS CURRENTLY MOVING ACROSS THE GULF WILL ENTER THE YUCATAN CHANNEL/NW CARIBBEAN LATE THURSDAY AFFECTING WESTERN CUBA. THE ATLANTIC OCEAN... MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS COVERS MOST OF THE W ATLC N OF 24N. DOPPLER RADAR SHOWS A STRONG LINE OF SHOWERS AND TSTMS JUST OFFSHORE THE E COAST OF FLORIDA N OF 27N. THIS SIGNIFICANT AMOUNT OF MOISTURE IS BEING ADVECTED FROM SW TO NE BY A SHORTWAVE TROUGH IN THE BAHAMAS. MOST OF THE SUBTROPICAL AND TROPICAL ATLC IS DOMINATED BY A LARGE STRONG MID-UPPER LEVEL HIGH CENTERED OVER THE SE CARIB. THIS RIDGE COVERS THE REGION BETWEEN 40W-70W. ABUNDANT DRY AND STABLE AIR ALOFT IS FOUND UNDER THE INFLUENCE OF THIS RIDGE. AN ELONGATED UPPER LEVEL TROUGH REMAINS OVER THE E ATLC AND EXTENDS FROM THE CANARY ISLANDS SWWD TO NEAR 10N45W. DRY AIR IS ALONG THE TROUGH AXIS WHILE PLENTY OF MID/UPPER LEVEL MOISTURE IS SEEN BETWEEN THE TROUGH AXIS AND THE W COAST OF AFRICA. TRANSVERSE HIGH CLOUDS ARE OVER THE CAPE VERDE ISLANDS. AT THE SURFACE...A COLD FRONT ENTERS THE E ATLC NEAR 32N25W THEN CONTINUES TO NEAR 27N38W WHERE IT BECOMES STATIONARY CONTINUING ALONG 24N50W 20N60W AND DISSIPATING N OF PUERTO RICO. A BAND OF MAINLY LOW CLOUDS AND SCATTERED SHOWERS IS ASSOCIATED WITH THE FRONT. A 1025 MB SFC HIGH IS BEHIND THE FRONTAL SYSTEM NEAR 31N64W. $$ GR