000 AXNT20 KNHC 151802 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SAT DEC 15 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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... FROM COASTAL LIBERIA NEAR 6N10W TO 5N31W TO 6N40W TO 3N47W AND INTO EXTREME NORTHEASTERN BRAZIL NEAR 3N51W. STRONG SHOWERS AND THUNDERSTORMS FROM 4N TO 7N BETWEEN 30W AND 34W. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE ELSEWHERE FROM THE EQUATOR TO 8N BETWEEN 29W AND 50W. ISOLATED MODERATE SHOWERS ARE FROM 4N TO 6N BETWEEN 15W AND 18W...AND FROM 5N TO 8N BETWEEN 55W AND 62W INCLUDING IN NORTHERN SECTIONS OF SURINAME...GUYANA...AND VENEZUELA. ...DISCUSSION... THE GULF OF MEXICO... THE MUCH-EXPECTED COLD FRONT HAS REACHED THE NORTHWESTERN GULF WATERS...FROM EAST TEXAS INTO NORTHEASTERN MEXICO JUST SOUTH OF THE TEXAS BORDER. THIS FRONT IS FORECAST TO CROSS THE GULF OF MEXICO AND TO MOVE THROUGH FLORIDA BY SUNDAY NIGHT. THE REMNANT LOW PRESSURE CENTER OF "OLGA" IS ABOUT 65 NM NORTH OF THE NORTHERN YUCATAN PENINSULA ALONG 88W AND IT IS MOVING NORTH NOW. THE FORECAST FOR THE "OLGA" LOW CENTER IS TO BE ABSORBED BY THE COLD FRONT IN THE NORTHWESTERN GULF OF MEXICO AS THE FRONT MOVES EASTWARD. ISOLATED MODERATE SHOWERS ARE ABOUT 80 NM NORTH- NORTHWEST OF THE "OLGA" LOW. ISOLATED TO WIDELY SCATTERED MODERATE SHOWERS ARE FROM 27N TO 31N BETWEEN 86W AND 90W IN THE NORTH CENTRAL GULF WATERS...AND NORTHWEST OF 30N91W 25N97W WITH THE COLD FRONT. THE CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL TROUGH IS ALONG 15N63W...IN THE EAST CENTRAL CARIBBEAN SEA WATERS...TO 13N71W NEAR ARUBA...TO 10N76W NEAR CARTAGENA COLOMBIA...TO 9N77W IN THE SOUTHWESTERN CORNER OF THE AREA JUST NORTH OF THE GULF OF URABA...CROSSING PANAMA INTO THE EASTERN PACIFIC OCEAN NEAR 7N81W. ISOLATED MODERATE SHOWERS ARE FROM 15N TO 16N BETWEEN 65W AND 68W...AND ELSEWHERE WITHIN 60 NM ON EITHER SIDE OF THE TROUGH. AN UPPER LEVEL RIDGE EXTENDS FROM SOUTHERN GUATEMALA ACROSS THE NORTHWESTERN CARIBBEAN SEA TO WESTERN CUBA. ISOLATED MODERATE SHOWERS HAVE FORMED AND/OR HAVE BEEN FORMING IN AN AREA OF UPPER LEVEL DIFFLUENT FLOW... AIDING THE PRECIPITATION DEVELOPMENT...FROM THE BORDER OF EASTERN HONDURAS/NORTHEASTERN NICARAGUA REMAINING IN EASTERN NICARAGUA SOUTHWARD TO NORTHEASTERN COSTA RICA. OTHER SHOWERS FORMED A FEW HOURS EARLIER SOUTH OF 11N BETWEEN 80W/81W...AND THEY HAVE BEEN MOVING SOUTHWESTWARD AND DISSIPATING DURING THE LAST FEW HOURS. BROKEN LOW TO MIDDLE LEVEL CLOUDS ARE WITHIN 45 NM ON EITHER SIDE OF THE LINE FROM WESTERN CUBA TO EASTERN HONDURAS. SHOWERS ARE POSSIBLE IN THIS LINE. UPPER LEVEL SOUTHWESTERLY WIND FLOW MOVES FROM VENEZUELA EAST OF 70W ACROSS THE EASTERN CARIBBEAN SEA ISLANDS...MOSTLY SOUTH OF GUADELOUPE. THE ATLANTIC OCEAN... BROAD MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW IS NORTH OF 18N WEST OF 30W. SOME OF THIS ANTICYCLONIC WIND FLOW IS RELATED TO THE UPPER LEVEL RIDGE FROM GUATEMALA ACROSS CUBA INTO THE ATLANTIC OCEAN. SOME OF IT IS RELATED TO ANTICYCLONIC FLOW TO THE WEST OF A MIDDLE TO UPPER LEVEL TROUGH THAT PASSES THROUGH 32N40W TO 27N43W. THE SOUTHERN END OF A COLD FRONT REACHES 31N33W. A TROUGH CONTINUES FROM 31N33W TO 29N37W AND 26N44W. A FAR EASTERN ATLANTIC OCEAN MIDDLE TO UPPER LEVEL TROUGH PASSES THROUGH 31N11W TO 26N16W TO 18N28W...EAST OF THE MADEIRA ARCHIPELAGO...PASSING OVER THE CANARY ISLANDS AND APPROACHING MOROCCO. UPPER LEVEL WEST-TO-SOUTHWEST WIND FLOW IS SOUTH OF 20N17W 17N33W 18N60W. $$ MT