000 AXNT20 KNHC 111145 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE JAN 11 2011 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ... THE ITCZ AXIS IS ANALYZED FROM 8N10W 5N20W 2N43W ACROSS THE EQUATOR NEAR 48W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 75/90 NM OF LINE FROM 7N20W TO 3N45W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL SHORTWAVE TROUGH IS MOVING ACROSS THE CENTRAL MISSISSIPPI VALLEY WITH A COLD FRONT INLAND OVER E MISSISSIPPI TO THE LOUISIANA BORDER E OF NEW ORLEANS. THIS FRONT IS NOT EXPECTED TO ENTER THE GULF WATERS. AN UPPER SHORTWAVE TROUGH IS IN THE W ATLC TRAILING A COLD FRONT AT 11/0900 UTC ACROSS THE FLORIDA PENINSULA THROUGH MELBOURNE TO FORT MYERS INTO THE GULF TO 26N84W WHERE IT BECOMES MEANDERS AS A STATIONARY/WARM FRONT ALONG 22N92W TO INLAND OVER S MEXICO E OF THE ISTHMUS OF TEHUANTEPEC. OVERCAST LOW CLOUDS WITH POSSIBLE ISOLATED SHOWERS AND PATCHES OF FOG ARE N OF 27N TO INLAND OVER THE N GULF COAST BETWEEN FLORIDA AND TEXAS. A STRONG SURFACE RIDGE IS BUILDING OVER THE CENTRAL PLAIN STATES AND IS EXPECTED TO PUSH OVER THE ENTIRE GULF LATER THIS AFTERNOON FORCING THE FRONT OUT OF THE GULF BY WED MORNING. CARIBBEAN SEA... BROAD UPPER RIDGE COVERS THE CARIBBEAN WITH THE RIDGE AXIS OVER THE LESSER ANTILLES INTO THE CENTRAL ATLC. THIS CONTINUES TO DRAW TROPICAL MOISTURE N OVER THE W/CENTRAL CARIBBEAN WHERE A LOW/MID LEVEL SWIRL HAS DEVELOPED ALONG THE COAST OF NICARAGUA GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 10N-14N W OF 80W TO INLAND OVER NICARAGUA AND N COSTA RICA. SIMILAR ACTIVITY IS WITHIN 30 NM ALONG THE COAST OF COLOMBIA AND PANAMA INCLUDING THE GULF OF URABA. BROKEN/OVERCAST HIGH CLOUDS REMAIN OVER THE N/CENTRAL CARIBBEAN WITHIN 150/175 NM OF LINE FROM 17N84W TO ACROSS CUBA AND HAITI NEAR 20N76W. FRESH/STRONG TRADE WINDS CONTINUE ACROSS THE CENTRAL AND E CARIBBEAN DUE TO THE TIGHT PRESSURE GRADIENT OF THE LOWER PRESSURE OVER SOUTH AMERICA AND THE SURFACE RIDGE OVER THE W ATLC INTO THE CENTRAL ATLC. THESE WINDS ARE EXPECTED TO PERSIST THROUGH FRI. A COLD FRONT WILL MOVE INTO THE NW CARIBBEAN EARLY WED BRINGING FRESH NE WINDS THAT GRADUALLY BECOME STRONG BY WED NIGHT. ATLANTIC OCEAN... THE SHORTWAVE UPPER TROUGH OVER THE W ATLC IS BEING ABSORBED IN INTO THE BROAD UPPER TROUGH DISCUSSED BELOW. THIS UPPER SHORTWAVE CONTINUES TO SUPPORT A 1014 MB LOW THAT AT 11/0900 UTC IS OFF THE SOUTH CAROLINA COAST AND A COLD FRONT THAT EXTENDS SW ACROSS FLORIDA NEAR MELBOURNE INTO THE GULF OF MEXICO. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE N OF 30N BETWEEN 73W-77W. SURFACE HIGH PRESSURE CONTINUES TO BUILD S OVER THE REMAINDER OF THE W ATLC N OF 24N BETWEEN 55W-75W AND ANCHORED BY A 1025 MB HIGH NEAR 30N67W. THE BROAD UPPER RIDGE THAT COVERS THE CARIBBEAN EXTENDS OVER THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC WITH THE AXIS EXTENDING ACROSS THE LESSER ANTILLES TO BEYOND 32N51W. THIS UPPER RIDGE IS DRAWING TROPICAL MOISTURE N ACROSS THE CENTRAL CARIBBEAN TO OVER THE W ATLC WITH BROKEN/OVERCAST HIGH CLOUDS WITHIN 175/200 NM OF LINE FROM ACROSS CUBA NEAR 21N75W TO 24N64W. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT COVERS THE TROPICAL ATLC. THE BROAD UPPER TROUGH OVER THE N/CENTRAL ATLC WITH THE LARGE UPPER LOW JUST E OF THE CANADIAN MARITIMES REMAINS N OF THE DISCUSSION AREA AND HAS ABSORBED THE SHORTWAVE UPPER TROUGH OVER THE W ATLC. THIS BROAD UPPER TROUGH CONTINUES TO TRAIL A COLD FRONT INTO THE CENTRAL ATLC NEAR 32N44W SW TO 26N52W WHERE IT DISSIPATES TO NEAR 23N59W. ISOLATED SHOWERS ARE WITHIN 120 NM E OF THE FRONT N OF 30N. A DEEP LAYERED RIDGE COVERS THE E ATLC WITH THE UPPER LEVELS ANCHORED NEAR 23N26W WITH A SURFACE 1030 MB HIGH N OF THE REGION BETWEEN MADEIRA ISLANDS AND THE AZORES THUS PRODUCING FAIR WEATHER FOR THE ATLC E OF FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW