000 AXNT20 KNHC 142344 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAR 14 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS ANALYZED FROM 07N11W CROSSING THE EQUATOR NEAR 19W TO 03S30W AND INTO NE BRAZIL NEAR 05S35W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 10W-21W. BROAD SCALE LOW-LEVEL TROUGHING IS EVIDENT OVER THE WESTERN TROPICAL ATLC S OF 08N BETWEEN 30W-50W FOCUSED IN THE VICINITY OF A SURFACE TROUGH ANALYZED FROM 07N50W TO THE NE BRAZIL COAST NEAR 01S46W. MOST OF THE SCATTERED MODERATE CONVECTION IS LOCATED EAST OF THE SURFACE TROUGH WITHIN 150 NM EITHER SIDE OF A LINE FROM THE EQUATOR NEAR 32W TO THE NORTHERN EXTENT OF THE SURFACE TROUGH NEAR 07N50W. THIS CONVECTIVE ACTIVITY IS LIKELY ENHANCED AS WELL DUE TO UPPER LEVEL DIFFLUENCE ON THE SOUTHERN PERIPHERY OF AN UPPER LEVEL RIDGE AXIS EXTENDING ALONG 04N30W TO 12N50W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES AN MIDDLE TO UPPER LEVEL LOW CENTERED OVER MISSOURI THIS EVENING WITH AN UPPER LEVEL TROUGH AXIS EXTENDING SW ACROSS EASTERN TEXAS AND INTO NORTHEAST MEXICO NEAR 25N102W. THE ASSOCIATED COLD FRONT AS OF 14/2100 UTC LIES ALONG THE IMMEDIATE TEXAS COAST FROM GALVESTON BAY NEAR 29N95W TO CORPUS CHRISTI BAY NEAR 28N97W. MOSAIC DOPPLER RADAR AND RECENT LIGHTNING DATA INDICATES SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 60 NM OF THE FRONT. THE FRONT IS FORECAST TO GRADUALLY PROGRESS EASTWARD OVER THE NEXT 24 HOURS WITH IMPACTS REMAINING MOSTLY N OF 25N AS THE WESTERN PORTION OF THE FRONT WEAKENS AND BECOMES DIFFUSE BY LATE TUESDAY OVER THE WESTERN GULF. THE REMAINDER OF THE GULF THIS EVENING SE OF THE COLD FRONT IS EXPERIENCING RELATIVELY LIGHT E-SE WINDS ON THE WESTERN PERIPHERY OF A SURFACE RIDGE WITH AXIS EXTENDING ALONG 28N BETWEEN THE SW NORTH ATLC AND 90W. AS THE FRONT EXITS NE OF THE REGION BY EARLY WEDNESDAY...SURFACE HIGH PRESSURE IS EXPECTED TO BUILD BACK IN ACROSS THE GULF THROUGH THE REMAINDER OF THE WEEK. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED EAST OF THE LEEWARD ISLANDS NEAR 12N50W THAT EXTENDS AN UPPER LEVEL RIDGE AXIS WESTWARD TO 15N80W WHICH IS PROVIDING THE CARIBBEAN SEA BASIN WITH DRY AIR AND MODERATE SUBSIDENCE ALOFT THIS EVENING. AT THE SURFACE...MODERATE TO FRESH E-NE TRADES ARE EXPECTED TO PREVAIL THROUGH FRIDAY WITH GLOBAL MODEL GUIDANCE INDICATING THOSE GRADUALLY INCREASING THROUGH THE WEEKEND DUE TO STRONGER HIGH PRESSURE SETTLING INTO THE SW NORTH ATLC LATE FRIDAY INTO EARLY SATURDAY. TOTAL PRECIPITABLE WATER IMAGERY THIS EVENING INDICATES HIGHER VALUES OF LOW-LEVEL MOISTURE IN THE ATMOSPHERE MOSTLY ACROSS THE WESTERN CARIBBEAN W OF 75W WITH AREAS OF ISOLATED SHOWERS OCCURRING S OF 19N W OF 80W...INCLUDING THE GULF OF HONDURAS AND PORTIONS OF EASTERN HONDURAS AND NE NICARAGUA. ATLANTIC OCEAN... MOSTLY WESTERLY ZONAL FLOW ALOFT IS LOCATED OVER THE SW NORTH ATLC W OF 55W. THIS FAIRLY BENIGN UPPER LEVEL PATTERN IS SUPPORTIVE OF A 1026 MB SURFACE HIGH CENTERED NEAR 30N72W WHICH IS PROVIDING MUCH OF THE REGION W OF 60W WITH FAIR CONDITIONS THIS EVENING. HOWEVER...A FEW ISOLATED SHOWERS ADVECTING SOUTHWESTWARD DUE TO NE WINDS ARE LOCATED S OF 22N BETWEEN 61W-75W. FARTHER EAST...A STATIONARY FRONT ENTERS THE DISCUSSION AREA NEAR 32N56W AND EXTENDS SOUTH ALONG 29N58W TO 24N57W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING EAST OF THE BOUNDARY FROM 24N-36N BETWEEN 46W AND THE FRONTAL BOUNDARY. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1027 MB HIGH CENTERED NEAR 34N39W. THE RIDGE COVERS MUCH OF THE AREA N OF 10N BETWEEN 20W-46W. AN UPPER LEVEL LOW STILL REMAINS LOCATED WEST OF THE IBERIAN PENINSULA CENTERED NEAR 40N14W THAT CONTINUES TO SUPPORT A COMPLEX AREA OF SURFACE LOW PRESSURE OVER SOUTHEASTERN EUROPE AND NORTHWESTERN AFRICA. A SURFACE TROUGH EXTENDS INTO THE DISCUSSION AREA NEAR 32N10W AND TRAILS SW TO 27N16W NEAR THE CANARY ISLANDS. POSSIBLE ISOLATED SHOWERS ARE OCCURRING N OF 27N E OF 19W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN