000 AXNT20 KNHC 150545 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU MAR 15 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 E TROPICAL ATLC NEAR 7N12W TO 6N15W WHERE THE ITCZ AXIS CONTINUES ALONG 4N24W 2N29W THEN S OF THE EQUATOR NEAR 34W INTO SOUTH AMERICA NEAR 2S44W. CLUSTERS OF ISOLATED MODERATE CONVECTION ARE FROM 5N TO S OF THE EQUATOR BETWEEN 14W-30W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE IS INLAND OVER E MEXICO ALONG THE COAST OF TEXAS TO INLAND OVER THE LOWER MISSISSIPPI VALLEY GIVING THE GULF NW FLOW ALOFT. A WEAK SURFACE TROUGH IS OVER THE W YUCATAN PENINSULA AT 15/0300 UTC EXTENDING FROM 22N89W TO NW GUATEMALA BUT IS NOT PRODUCING ANY SIGNIFICANT WEATHER. A SURFACE RIDGE DOMINATES THE GULF EXTENDING FROM THE W ATLC AND ANCHORED BY A 1025 MB HIGH OFF THE COAST OF PENSACOLA FLORIDA. THE FLOW AROUND THIS HIGH HAS PUSHED THE SEA FOG INLAND OVER S MISSISSIPPI. THIS IS LEAVING THE GULF UNDER CLEAR SKIES AGAIN TONIGHT. SURFACE RIDGE WILL PREVAIL THROUGH MON. CARIBBEAN SEA... AN UPPER TROUGH EXTENDS JUST E OF FLORIDA INTO THE NW CARIBBEAN ACROSS CENTRAL CUBA TO THE CENTRAL COAST OF HONDURAS COVERING THE AREA N OF 15N W OF 77W. A BROAD UPPER RIDGE ANCHORED OVER THE TROPICAL ATLC DOMINATES THE REMAINDER OF THE CARIBBEAN. MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR PREVAIL ACROSS THE CARIBBEAN WITH THE EXCEPTION OF THE FAR SE CARIBBEAN WHERE ISOLATED SHOWERS ARE S OF 13N BETWEEN 61W-69W INCLUDING THE WINDWARD AND ABC ISLANDS. TIGHT PRESSURE GRADIENT IS PRODUCING FRESH TO STRONG NE TO E TRADE WINDS ACROSS THE BASIN. THESE TRADE WINDS ARE BANKING LOW CLOUDS WITH SCATTERED SHOWERS OVER THE SW CARIBBEAN S OF 12N BETWEEN 76W-80W TO INLAND OVER PANAMA...AND WITHIN 45 NM ALONG THE IMMEDIATE COAST AND INLAND OVER THE REMAINDER OF PANAMA AND ALL OF COSTA RICA. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OROGRAPHICALLY INDUCED OVER THE HIGHER ELEVATIONS OF PUERTO RICO/HISPANIOLA AND INLAND OVER CENTRAL AMERICA FROM N NICARAGUA TO S MEXICO LEAVING THE REMAINDER OF THE CARIBBEAN WATERS WITH MOSTLY FAIR WEATHER AGAIN TONIGHT. THE LITTLE CHANGE IS EXPECTED THROUGH MON. ATLANTIC OCEAN... AN UPPER TROUGH EXTENDS OFF THE EASTERN SEABOARD JUST OFF THE FLORIDA COAST TO ACROSS CENTRAL CUBA INTO THE NW CARIBBEAN GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE N BAHAMA ISLANDS FROM 23N-27N BETWEEN 72W-80W. A SURFACE RIDGE COVERS THE W ATLC FROM THE CENTRAL ATLC ANCHORED BY A 1033 MB HIGH ABOUT 500 NM E OF BERMUDA. A NARROW UPPER TROUGH IS OVER THE CENTRAL ATLC EXTENDING THROUGH 32N37W TO NEAR 25N51W SUPPORTING A DISSIPATING STATIONARY FRONT THAT ENTERS THE E/CENTRAL ATLC NEAR 32N39W ALONG 30N39W TO 26N42W AND A SURFACE TROUGH THAT EXTENDS FROM 26N48W TO 22N51W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 24N-27N BETWEEN 44W-48W. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC S OF 25N E OF 60W WITH A NARROW RIDGE AXIS EXTENDING ALONG 21W N OF 25N. A SURFACE RIDGE DOMINATES THE E ATLC ANCHORED BY A 1031 MB HIGH JUST S OF THE AZORES. THE LAST VISIBLE SATELLITE IMAGES SHOW THE AREA OF DISSIPATING AFRICAN DUST COVERING THE E TROPICAL ATLC FROM THE ITCZ TO 28N E OF 50W. W ATLC SURFACE RIDGE WILL REMAIN THROUGH MON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW