000 AXNT20 KNHC 091744 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST TUE JAN 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... ITCZ AXIS IS ALONG 2N AT THE PRIME MERIDIAN...3N16W 2N30W 3N45W 2N51W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 1N-6N BETWEEN 30W-60W. A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION IS NEAR 1S37W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH REMAINS OVER THE E US AND THE NE GULF MOVING INTO THE NW ATLC RESULTING IN MOSTLY WESTERLY UPPER WINDS ACROSS THE GULF. THESE WINDS ARE TRANSPORTING ABUNDANT UPPER LEVEL MOISTURE ACROSS THE GULF MAINLY NORTH OF 25N. AS OF 1500 UTC... THE ATTENDANT COLD FRONT IS SE OF THE AREA OVER WESTERN CUBA. COLD STRATOCUMULUS CLOUDS COVER THE GULF...PARTICULARLY SOUTH OF 25N INCLUDING THE BAY OF CAMPECHE. BROKEN TO OVERCAST LOW CLOUDS ARE POOLED AGAINST THE SIERRA MADRE DEL SUR IN MEXICO. MODERATE TO STRONG NORTH WINDS WITH COOLER TEMPERATURES AND LOW DEW POINTS ARE FOUND BEHIND THE FRONTAL BOUNDARY. A SURFACE RIDGE CONTINUES TO BUILD ACROSS THE GULF AND NE MEXICO WITH A 1035 MB HIGH ALONG THE TEXAS/MEXICO BORDER. MODERATE/STRONG NORTHERLY SURFACE WINDS WILL REMAIN ACROSS THE GULF THROUGH TONIGHT BECOMING WEAKER AND MORE EASTERLY AS THE SURFACE RIDGE GRADUALLY MOVES E ACROSS THE SE US. HIGH PRES WILL REMAIN IN CONTROL OF THE WEATHER PATTERN ACROSS THE GULF THROUGH AT LEAST FRIDAY. ON THIS DAY...SLY RETURN FLOW WILL DEVELOP AHEAD OF THE NEXT COLD FRONT. CARIBBEAN SEA... NARROW UPPER RIDGE EXTENDS FROM CENTRAL AMERICA NE TO OVER W CUBA/THE BAHAMAS. ANOTHER UPPER LEVEL RIDGE EXTENDING FROM A HIGH ANCHORED OVER NE BRAZIL COVERS COLOMBIA...VENEZUELA AND THE SE CORNER OF THE BASIN. IN BETWEEN...THERE IS AN UPPER TROUGH THAT RUNS FROM HISPANIOLA TO COSTA RICA. STRONG SUBSIDENCE AND VERY DRY AIR REMAIN IN CONTROL OF THE CARIBBEAN. EASTERLY TRADE WINDS HAVE WEAKEN AS THE HIGH PRESSURE OVER THE ATLC CONTINUES TO SHIFT E AHEAD OF THE COLD FRONT THAT REACHED WESTERN CUBA THIS MORNING. THE CITY OF HAVANA REPORTED NLY WINDS OF AROUND 15 KT. LATEST SAT PICTURES SHOWS THAT THE LEADING EDGE OF THE FRONTAL BOUNDARY IS ACROSS THE ANDROS ISLAND IN THE BAHAMAS AND WESTERN CUBA CONTINUING MAINLY S ALONG THE YUCATAN CHANNEL/ PENINSULA AND BELIZE. SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS CAN BE EXPECTED WITH THE PASSAGE OF THE FRONT. THE TRADE WINDS ARE EXPECTED TO INCREASE AGAIN THU THROUGH SAT AS HIGH PRES BUILD N OF AREA AND MOVES E. ATLANTIC OCEAN... DEEP LAYERED TROUGH OVER THE US AND NE GULF OF MEXICO EXTENDS OVER THE FAR W ATLC. THE ASSOCIATED COLD FRONT ENTERS THE AREA NEAR 32N70W...THEN CONTINUES SWWD ACROSS THE NORTHERN BAHAMAS AND W CUBA. DOPPLER RADAR DEPICTS SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE STRAITS OF FLORIDA ASSOCIATED WITH THE FRONTAL BOUNDARY. NARROW UPPER RIDGE IS IN THE W ATLC EXTENDING FROM ACROSS W CUBA TO NEAR 28N67W. STRONG SUBSIDENCE AND DRY AIR DOMINATES THE REMAINDER OF THE W ATLC W OF 60W. AN UPPER LOW REMAINS NEAR 22N60W WITH A TROUGH EXTENDING E AND NE TO NEAR THE CANARY ISLANDS. WEAK SURFACE REFLECTION IN THE FORM OF A SURFACE TROUGH ALSO REMAINS OVER THE ATLC AND EXTENDS FROM 26N54W TO THE VIRGIN ISLANDS NEAR 19N64W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ON THE NORTHERN END OF THE TROUGH. A BROAD HIGH AMPLITUDE UPPER RIDGE CONTINUES TO DOMINATE THE TROPICS WITH THE RIDGE AXIS EXTENDING N TO 23N40W COVERING THE AREA BETWEEN THE LESSER ANTILLES AND THE COAST OF W AFRICA. JET STREAM WITH WINDS OF 90 TO 110 KT EXTENDS ALONG THE N PERIPHERY OF THIS UPPER RIDGE. AT THE SURFACE...HIGH PRESSURE DOMINATES THE ENTIRE ATLC E OF THE FRONT IN THE FAR W ATLC WITH AN ADDITIONAL WEAKNESS ALONG THE SURFACE TROUGH MENTIONED ABOVE. A 1031 MB HIGH IS OVER THE CENTRAL ATLC NEAR 36N42W. $$ GR