000 AXNT20 KNHC 060559 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU DEC 06 2012 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE FAR E TROPICAL ATLC NEAR 8N13W TO 7N17W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 5N27W 8N41W 10N51W TO SOUTH AMERICA NEAR 7N59W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 90 NM N OF THE ITCZ BETWEEN 25W-29W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 3N-8N BETWEEN 15W-25W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF THE ITCZ BETWEEN 43W-46W. ...DISCUSSION... GULF OF MEXICO... AN UPPER TROUGH EXTENDS ACROSS MISSISSIPPI INTO THE GULF TO AN UPPER LOW NEAR 27N89W CONTINUING S TO THE BAY OF CAMPECHE NEAR VERA CRUZ MEXICO SUPPORTING A WEAK FRONTAL BOUNDARY THAT AT 06/0300 UTC EXTENDS ACROSS PENSACOLA FLORIDA TO A 1016 MB SURFACE LOW NEAR 28N89W WITH A COLD FRONT CONTINUING SW ALONG 26N91W TO 22N97W. A SURFACE TROUGH PRECEDES THE FRONT EXTENDING FROM THE LOW ALONG 26N89W TO 20N94W. SCATTERED SHOWERS/ THUNDERSTORMS ARE WITHIN 90 NM E OF THE FRONT/LOW BETWEEN 26N-30N WITH ISOLATED SHOWERS WITHIN 60 NM E OF THE TROUGH S OF 22N. A SURFACE RIDGE IS BEGINNING TO BUILD S BEHIND THE FRONT ANCHORED BY A 1021 MB HIGH OVER ARKANSAS. ISOLATED SHOWERS DOT THE E GULF WITHIN 120 NM OF LINE FROM 27N87W TO THE STRAITS OF FLORIDA NEAR 24N81W INCLUDING S FLORIDA AND THE FLORIDA KEYS. SURFACE LOW WILL REMAIN NEARLY STATIONARY THROUGH TONIGHT THEN BEGIN TO DRIFT NW AND INLAND FRI BEFORE DISSIPATING WHILE THE FRONT STALLS AND DISSIPATES OVER THE W/CENTRAL GULF THROUGH THU. SURFACE RIDGE WILL BUILD OVER SE CONUS THROUGH THE WEEKEND. CARIBBEAN SEA... A BROAD UPPER RIDGE IN THE TROPICAL ATLC EXTENDS A RIDGE AXIS FROM AN UPPER HIGH NEAR 10N44W ALONG THE N COAST OF SOUTH AMERICA TO OVER COSTA RICA NEAR 11N84W GIVING THE CARIBBEAN MAINLY SW TO W FLOW ALOFT. A SHEAR LINE EXTENDS FROM THE CENTRAL ATLC INTO THE CARIBBEAN OVER MARTINIQUE THEN ALONG 13N65W 14N74W TO 12N78W GENERATING SCATTERED SHOWERS N OF THE SHEAR LINE TO THE GREATER ANTILLES AND N OF 18N BETWEEN 78W-84W. BROAD SURFACE RIDGE OVER THE W ATLC WILL MAINTAIN LIGHT TO MODERATE TRADE WINDS ACROSS MOST OF THE REGION THROUGH FRI. ATLANTIC OCEAN... A SURFACE TROUGH IS OVER THE BAHAMA ISLANDS EXTENDING FROM 28N76W TO THE COAST OF CUBA NEAR 22N77W GENERATING SCATTERED SHOWERS WITHIN 180 NM E OF THE WAVE AND ISOLATED SHOWERS W OF THE WAVE TO THE COAST OF FLORIDA. AN UPPER RIDGE EXTENDS OVER THE W ATLC ALONG 69W FROM 20N TO BEYOND 32N WITH A WEAK SURFACE RIDGE COVERING THE REMAINDER OF THE W ATLC. BROAD UPPER TROUGH COVERS THE E/CENTRAL ATLC N OF 20N BETWEEN 35W-55W SUPPORTING A 1002 MB STORM CENTER NEAR 31N41W WITH A DEVELOPING FRONT EXTENDING ALONG 26N42W 21N44W TO 16N58W WHERE A SHEAR LINE EXTENDS INTO THE CARIBBEAN ACROSS MARTINIQUE. A WARM FRONT EXTENDS FROM THE LOW ENE BEYOND 32N38W. AN UPPER RIDGE EXTENDS FROM THE TROPICAL ATLC AND AN UPPER HIGH NEAR 10N44W ALONG 27N27W TO BEYOND 32N21W ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 225/250 NM OF LINE FROM 17N42W TO BEYOND 32N34W. A SURFACE RIDGE DOMINATES THE REMAINDER OF THE E ATLC N OF 15N E OF 35W ANCHORED BY A 1025 MB HIGH BETWEEN THE CANARY AND THE MADEIRA ISLANDS NEAR 31N16W. SURFACE RIDGE WILL SHIFT E AND COLLAPSE THROUGH FRI AS A WEAK COLD FRONT BRUSHES PAST THE NORTHERN WATERS. A SURFACE TROUGH OVER THE BAHAMAS WILL DRIFT W AND AMPLIFY THROUGH FRI AS IT MOVES OVER FLORIDA. STRONG HIGH PRESSURE WILL BUILD NE OF THE AREA FRI THROUGH SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW