000 AXNT20 KNHC 071747 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST THU JAN 07 2010 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND 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 THE 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 6N10W 3N30W CROSSING THE EQUATOR NEAR 43W AND INTO NE BRAZIL NEAR 2S48W. SCATTERED MODERATE CONVECTION IS FROM 2N-7N BETWEEN 22W-38W. SIMILAR CONVECTION IS FROM THE EQUATOR TO 2N BETWEEN 46W-50W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A COLD FRONT ENTERS THE NW GULF NEAR CAMERON LOUISIANA AND EXTENDS SW ALONG 27N96W TO BROWNSVILLE TEXAS AND THEN INLAND OVER NORTHERN MEXICO. MOSAIC DOPPLER RADAR INDICATES SCATTERED SHOWERS AND POSSIBLE ISOLATED TSTMS ARE WITHIN 90 NM EITHER SIDE OF THE FRONTAL BOUNDARY. A PRE-FRONTAL SURFACE TROUGH IS ANALYZED FROM THE COLD FRONT NEAR BROWNSVILLE ALONG THE MEXICO GULF COAST TO NEAR TUXPAN. STRONG SE TO S SURFACE WINDS UP TO 20 KT ARE ACROSS THE WESTERN GULF W OF 90W. NW OF THE FRONT...GALE FORCE CONDITIONS ARE EXPECTED WITHIN 24 HOURS AS A STRONG SURFACE RIDGE...CURRENTLY LOCATED ACROSS THE CENTRAL PLAINS BUILDS IN ACROSS THE NORTHERN AND WESTERN GULF THROUGH SATURDAY. THE REMAINDER OF THE GULF E OF 90W CONTINUES TO BE IMPACTED BY A SURFACE RIDGE ANCHORED ON A 1025 MB HIGH CENTERED OVER THE BIG BEND REGION OF FLORIDA NEAR 29N83W. AS THE COLD FRONT APPROACHES FROM THE WEST...THIS RIDGE IS FORECAST TO WEAKEN SLIGHTLY AND GRADUALLY SLIDE EASTWARD INTO THE W ATLC BY EARLY FRIDAY. ALOFT...MOSTLY ZONAL WESTERLY FLOW DOMINATES ACROSS THE GULF OF MEXICO PROVIDING A FAIRLY PROGRESSIVE ENVIRONMENT FOR THE COLD FRONT MOVING ACROSS THE GULF BASIN. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION DOMINATES THE ENTIRE CARIBBEAN SEA AND IS PROVIDING A RELATIVELY SUBSIDENT ENVIRONMENT ACROSS THE ENTIRE BASIN IN THE MIDDLE TO UPPER LEVELS. THIS UPPER HIGH IS CENTERED NEAR 11N75W AND EXTENDS UPPER LEVEL RIDGING TO 20N AND EASTWARD INTO THE TROPICAL ATLC TO 40W. HOWEVER...AT THE SURFACE AND LOWER LEVELS...A SHALLOW STATIONARY FRONT ENTERS THE BASIN ACROSS FAR EASTERN PUERTO RICO NEAR 18N66W AND EXTENDS TO 16N71W. IT CONTINUES AS A SHEAR LINE ACROSS THE CENTRAL AND WESTERN CARIBBEAN ALONG 16N75W TO THE COAST OF COSTA RICA NEAR 10N83W AND INTO THE E PACIFIC REGION. SCATTERED SHOWERS ARE OCCURRING WITHIN 60 NM EITHER SIDE OF THE STATIONARY FRONT...INCLUDING PUERTO RICO...THE US/UK VIRGIN ISLANDS...AND ADJACENT COASTAL WATERS. ISOLATED SHOWERS ARE ALSO FOUND WITHIN 90 NM NORTH OF THE SHEAR LINE...WITH OTHER ISOLATED SHOWER ACTIVITY OCCURRING OVER PORTIONS OF THE NW CARIBBEAN AND CENTRAL AMERICA...MOST NOTABLY IN THE GULF OF HONDURAS AND NEARBY BELIZE. ATLANTIC OCEAN... A DEEP LAYERED TROUGH REMAINS NORTH OF THE W ATLC DISCUSSION AREA WITH WESTERLY UPPER LEVEL FLOW LOCATED MAINLY W OF 60W. THIS UPPER LEVEL TROUGHING SUPPORTS A COLD FRONT THAT ENTERS THE CENTRAL ATLC NEAR 32N46W AND EXTENDS SW TO 22N63W THEN CONTINUES AS A STATIONARY FRONT INTO A 1016 MB LOW CENTERED NEAR 20N64W. THIS STATIONARY BOUNDARY THEN EXTENDS SW ACROSS EASTERN PUERTO RICO AND INTO THE CENTRAL CARIBBEAN SEA. SCATTERED SHOWERS ARE OCCURRING WITHIN 200 NM EITHER SIDE OF THE FRONT WITH POSSIBLE ISOLATED TSTMS REMAINING N OF 28N AND EAST OF THE COLD FRONT. AS THIS FRONT CONTINUES TO MOVE OFF TO THE EAST...A WEAK SURFACE RIDGE...CURRENTLY ANCHORED BY A 1025 MB HIGH CENTERED OVER NORTHERN FLORIDA...IS FORECAST TO BUILD INTO THE W ATLC WATERS THROUGH EARLY FRIDAY. FARTHER EAST ACROSS THE REMAINDER OF THE TROPICAL AND EASTERN ATLC...A SURFACE RIDGE DOMINATES ANCHORED BY A 1023 MB HIGH CENTERED NEAR 27N34W BRINGING GENERALLY FAIR WEATHER SE OF A LINE FROM 32N37W TO THE LEEWARD ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE. $$ HUFFMAN