000 AXNT20 KNHC 100555 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SAT MAR 10 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 AFRICA INTO THE E TROPICAL ATLC NEAR 7N12W CONTINUING ALONG 3N13W TO THE EQUATOR NEAR 16W WHERE THE ITCZ AXIS CONTINUES ALONG THE EQUATOR TO 27W THEN TURNS S OF THE EQUATOR TO THE COAST OF BRAZIL NEAR 3S40W. ISOLATED SHOWERS ARE WITHIN 45 NM OF LINE FROM 5N13W TO 1N24W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE DOMINATES THE GULF EXTENDING ACROSS S MEXICO NEAR VERACRUZ TO OVER NE FLORIDA. HOWEVER...A BROAD UPPER TROUGH IS OVER THE NE CONUS INTO THE NW ATLC SUPPORTING A COLD FRONT THAT EXTENDS THROUGH THE W ATLC ACROSS FLORIDA INTO THE GULF OF MEXICO AT 10/0300 UTC NEAR SAINT AUGUSTINE TO CEDAR KEY TO 28N89W WHERE IT BECOMES STATIONARY ALONG 28N94W THEN S ALONG 22N95W TO INLAND OVER MEXICO NEAR 20N97W. THE UPPER RIDGE IS DRAWING TROPICAL MOISTURE ACROSS MEXICO INTO THE NW GULF ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 25N W OF 93W WITH ISOLATED SHOWERS N OF THE FRONT E OF 93W AND W OF THE STATIONARY FRONT S OF 25N. FAIR WEATHER IS ELSEWHERE ACROSS THE REMAINDER OF THE GULF. A SURFACE RIDGE IS BUILDING S OVER THE TEXAS INTO THE GULF ANCHORED BY A 1035 MB HIGH OVER THE GREAT LAKES. THE STATIONARY FRONT IS EXPECTED TO MOVE NW TO INLAND OVER LOUISIANA AS WARM FRONT LATER TODAY. CARIBBEAN SEA... AN UPPER TROUGH EXTENDS FROM THE W ATLC INTO THE CARIBBEAN ACROSS CUBA/HISPANIOLA TO COSTA RICA/PANAMA DOMINATING MOST OF THE CARIBBEAN BASIN WITH STRONG SUBSIDENCE AND DRY STABLE AIR COVERING THE AREA W OF 68W. AN UPPER RIDGE IN THE W TROPICAL ATLC COVERS THE FAR E CARIBBEAN DRAWING MOISTURE ALOFT ACROSS THE FAR E CARIBBEAN AND LESSER ANTILLES GENERATING ISOLATED SHOWERS S OF 16N BETWEEN 59W-68W INCLUDING THE WINDWARD ISLANDS. A TIGHT PRESSURE GRADIENT IS ESTABLISHED ACROSS THE CARIBBEAN BETWEEN THE HIGHER PRESSURE OVER THE ATLC AND THE LOWER PRESSURE OVER SOUTH AMERICA PRODUCING FRESH TO STRONG EASTERLY TRADE WINDS WHICH ARE BANKING LOW CLOUDS WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER THE GULF OF HONDURAS S OF 18N W OF 84W. OTHERWISE FAIR WEATHER IS ELSEWHERE ACROSS THE REMAINDER OF THE CARIBBEAN. STRONG HIGH PRESSURE OVER THE ATLC WILL WEAKEN AND SHIFT E ALLOWING TRADE WINDS TO DIMINISH ACROSS ALL BUT THE CENTRAL CARIBBEAN THROUGH WED. ATLANTIC OCEAN... A BROAD UPPER TROUGH IS OVER THE NE CONUS INTO THE NW ATLC SUPPORTING A COLD FRONT THAT EXTENDS INTO THE W ATLC AT 10/0300 UTC NEAR 32N76W ACROSS FLORIDA INTO THE GULF OF MEXICO NEAR SAINT AUGUSTINE WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM E OF THE FRONT. A WEAK SURFACE TROUGH IS ALONG THE E COAST OF FLORIDA FROM 29N80W TO 26N81W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM EITHER SIDE OF THE SURFACE TROUGH. AN UPPER RIDGE EXTENDS ACROSS NE FLORIDA TO BEYOND BERMUDA BEING AMPLIFIED BY AN UPPER TROUGH THAT EXTENDS THROUGH 32N58W ACROSS CUBA/HISPANIOLA INTO THE CARIBBEAN SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 30N63W TO 23N64W. AN AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IS FROM 22N-28N BETWEEN 55W-63W. NEAR ZONAL WESTERLY FLOW ALOFT DOMINATES THE REMAINDER OF THE ATLC E OF 50W. HOWEVER...A LARGE UPPER LOW IS N OF THE DISCUSSION AREA SUPPORTING A COLD FRONT THAT ENTERS THE E ATLC NEAR 32N26W TO 27N30W WHERE A SHEAR AXIS IS ANALYZED ALONG 24N39W TO 24N49W. ISOLATED SHOWERS ARE WITHIN 45 NM E OF THE FRONT. A BROAD SURFACE RIDGE IS ANCHORED BETWEEN THE W AND E ATLC FRONTS BY A 1036 MB HIGH NEAR 35N48W. A LARGE UPPER RIDGE COVERS MOST OF THE TROPICAL ATLC ANCHORED OFF THE COAST OF BRAZIL NEAR 3N43W COVERING THE AREA S OF 20N BETWEEN 30W-65W. STRONG HIGH PRESSURE RIDGE OVER THE CENTRAL ATLC WILL SHIFT E ALLOWING WINDS TO DIMINISH TODAY. COLD FRONT IN THE W ATLC WILL REACH 32N70W TO CENTRAL FLORIDA LATE TODAY AND FROM 32N60W TO 27N80W EARLY SUN THEN WEAKEN AND BECOME DIFFUSE LATE SUN. NEW SURFACE RIDGE WILL BUILD IN MON AND TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW