000 AXNT20 KNHC 111745 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON APR 11 2013 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA-BISSAU NEAR 11N15W TO 7N17W 4N18W. THE ITCZ CONTINUES FROM 4N18W TO 2N20W..CROSSING THE EQUATOR ALONG 27W...TO 1S35W AND TO THE EQUATOR AGAIN ALONG 38W. CONVECTIVE PRECIPITATION... SCATTERED TO NUMEROUS STRONG FROM 1N TO 2N BETWEEN 6W AND 8W...SCATTERED MODERATE TO ISOLATED STRONG FROM 1S TO 2N BETWEEN 35W AND 41W...AND IN BRAZIL AND ITS COASTAL WATERS FROM 3S TO THE EQUATOR BETWEEN 44W AND 47W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS INLAND IN TEXAS. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH LOUISIANA NEAR 29N93W...ACROSS THE WATERS OF THE NORTHWESTERN GULF OF MEXICO...TO THE COAST OF MEXICO NEAR 23N98W...NORTHWESTWARD TO 26N100W AND BEYOND THE TEXAS BIG BEND. CONVECTIVE PRECIPITATION THAT IS RELATED TO THE TROUGH AND FRONT APPEARS TO BE INLAND MOSTLY...FROM THE WATERS OFF THE SOUTHEASTERN COAST OF LOUISIANA NEAR 28N90W...NORTHWARD THROUGH LOUISIANA...AND EVEN POSSIBLY ALONG THE BORDER OF TEXAS AND LOUISIANA. RAINSHOWERS ARE POSSIBLE ALSO IN THE GULF OF MEXICO TO THE WEST AND NORTHWEST OF 19N96W 24N91W 30N87W. AN UPPER LEVEL RIDGE EXTENDS FROM NORTH CENTRAL GUATEMALA...ACROSS THE YUCATAN PENINSULA...INTO THE EAST CENTRAL GULF OF MEXICO...THROUGH THE NORTHEASTERN CORNER OF THE AREA...BEYOND THE FLORIDA BIG BEND AND THE FLORIDA PANHANDLE. THE SKIES IN THE DEEP SOUTH OF TEXAS ARE CLEARING GRADUALLY...AFTER THE PASSAGE OF THE COLD FRONT. SOME LOW CLOUD CEILINGS REMAIN THERE. LOW LEVEL AND MIDDLE LEVEL CLOUD CEILINGS COVER PARTS OF THE HOUSTON METROPOLITAN AREA...GALVESTON...AND BEAUMONT/PORT ARTHUR IN THE UPPER TEXAS GULF COAST AREA. CLEARING SKIES/FAIRER SKIES ARE BETWEEN HOUSTON AND THE DEEP SOUTH OF TEXAS. PRECIPITATION COVERS THE WESTERN HALF OF COASTAL LOUISIANA. LOW CLOUD CEILINGS AND LOW VISIBILITIES WITH HAZE AND FOG COVER THE REST OF COASTAL LOUISIANA. LOW CLOUD CEILINGS COVER THE COASTAL PLAINS FROM LOUISIANA TO APALACHICOLA BAY FLORIDA...AND EVENTUALLY TO SARASOTA FLORIDA. SCATTERED TO BROKEN LOW CLOUDS COVER THE REST OF FLORIDA TO THE SOUTH OF SARASOTA. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... THE TEXAS COASTAL STATIONS... SCATTERED TO BROKEN LOW CLOUDS COVER THE AREA. THE ICAO STATION KGVX WAS REPORTING A CLOUD CEILING AT 7500 FEET AT 11/1455 UTC. LOW CLOUD CEILINGS ARE OBSERVED AT THE ICAO STATIONS KHQI...KGBK...KEIR...KSPR...AND KMYT. ICAO STATION KVBS REPORTS A MIDDLE LEVEL CLOUD CEILING. SCATTERED LOW CLOUDS ARE BEING OBSERVED AT ICAO STATION KEHC. ICAO STATION KVNP REPORTS SCATTERED TO BROKEN LOW CLOUDS AND MIDDLE LEVEL CLOUDS. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2... AND THE OFFSHORE FORECAST...MIAOFFNT4...FOR MORE DETAILS ABOUT THE COLD FRONT 29N92W 23N98W. EXPECT 20 TO 30 KNOT NORTH WINDS AND SEA HEIGHTS REACHING 12 FEET TO THE WEST OF THE FRONT. EXPECT ALSO 20 KNOT WINDS OR LESS AND SEA HEIGHTS REACHING 8 FEET TO THE NORTH OF 24N TO THE EAST OF THE FRONT TO 88W. THE CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL RIDGE EXTENDS FROM COLOMBIA NEAR 8N76W...TO PANAMA NEAR 9N80W...THROUGH WESTERN NICARAGUA...TO THE YUCATAN PENINSULA. THIS RIDGE MERGES MORE OR LESS WITH THE RIDGE THE RIDGE/ ANTICYCLONIC WIND FLOW THAT COVERS THE GULF OF MEXICO. THE BASE OF A MIDDLE LEVEL TO UPPER LEVEL TROUGH REACHES 14N63W IN THE EASTERN CARIBBEAN SEA. THE TROUGH IS ALONG 21N59W 17N60W 14N63W. THE MONSOON TROUGH IS ALONG 8N/9N BETWEEN 76W IN COLOMBIA BEYOND 86W INTO THE EASTERN PACIFIC OCEAN. ANY CONVECTIVE PRECIPITATION IS IN THE EASTERN PACIFIC OCEAN TO THE SOUTH OF 7N BETWEEN 80W AND 90W. RAINSHOWERS ARE POSSIBLE TO THE NORTHEAST OF 21N82W 16N74W 13N70W. THE CLOUDS THAT ARE IN THIS AREA ARE MOVING TO THE WEST AND NORTHWEST WITH THE LOW LEVEL WIND FLOW. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT THE 20 TO 25 KNOT WINDS AND SEA HEIGHTS REACHING 10 FEET FROM 11N TO 15N BETWEEN 68W AND 77W. ALSO EXPECT WIND SPEEDS TO BE 20 KNOTS OR LESS AND SEA HEIGHTS REACHING 8 FEET FROM 10N TO 16N BETWEEN 72W AND 79W. A SECOND AREA OF INTEREST IS FOR 20 TO 25 KNOT WINDS AND SEA HEIGHTS REACHING 9 FEET TO THE SOUTH OF 20N TO THE WEST OF 84W INCLUDING IN THE GULF OF HONDURAS. THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N33W TO 30N43W...TO 25N52W AND 23N59W. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N22W TO 29N30W. A STATIONARY FRONT CONTINUES FROM 29N30W TO 26N40W 24N50W AND 24N62W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE RAINSHOWERS ARE WITHIN 75 NM TO 150 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N14W TO 31N31W 27N45W 24N55W AND 25N65W. A MIDDLE LEVEL ANTICYCLONIC CIRCULATION CENTER IS NEAR 29N60W. ANTICYCLONIC WIND FLOW IS FROM 22N TO 34N BETWEEN 54W AND 67W. MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW MOVES FROM THE EASTERN SIDE OF THE GULF OF MEXICO RIDGE...TOWARD THE BASE OF A TROUGH THAT IS NEAR 14N63W IN THE EASTERN CARIBBEAN SEA. THE TROUGH IS ALONG 21N59W 17N60W 14N63W. A SURFACE RIDGE EXTENDS FROM A 1024 MB HIGH PRESSURE CENTER THAT IS NEAR 33N32W...TO 31N48W... TO A 1024 MB HIGH PRESSURE CENTER THAT IS NEAR 30N63W TOWARD THE SOUTH CAROLINA COAST. A 1024 MB HIGH PRESSURE CENTER IS NEAR 28N28W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2... FOR MORE DETAILS ABOUT THE 18 HOUR FORECAST OF 20 TO 25 KNOT WINDS AND SEA HEIGHTS LOWER THAN 8 FEET TO THE NORTH OF 29N TO THE WEST OF 75W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT