000 AXNT20 KNHC 211149 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE AUG 21 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION NINE AT 21/1200 UTC IS NEAR 15.1N 51.8W...OR ABOUT 645 MI...1035 KM E OF GUADELOUPE. THE DEPRESSION IS MOVING WESTWARD AT 17 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 30 KT WITH GUSTS TO 40 KT. PLEASE READ THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE PUBLIC ADVISORY... MIATCPAT4/ WTNT34 KNHC FOR MORE DETAILS. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 13N TO 15.5N BETWEEN 51W AND 53W...SCATTERED MODERATE TO ISOLATED STRONG FROM 13N TO 18N BETWEEN 54W AND 55W AND FROM 9N TO 12N BETWEEN 47W AND 53W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND OTHER POSSIBLE RAINSHOWERS ARE ELSEWHERE FROM 10N TO 20N BETWEEN 40W AND 57W. IT IS POSSIBLE THAT THIS SYSTEM MAY REACH THE LEVEL OF TROPICAL STORM NEAR THE EAST CENTRAL CARIBBEAN SEA ISLANDS ABOUT 36 HOURS INTO THE FUTURE. TROPICAL STORM WARNINGS HAVE BEEN INITIATED BY THE INDIVIDUAL GOVERNMENTS OF THE EASTERN CARIBBEAN SEA ISLANDS FROM DOMINICA AND GUADELOUPE NORTHWARD. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 28W/29W FROM THE 1010 MB LOW PRESSURE CENTER THAT IS NEAR 10N ALONG THE WAVE TO 17N. NUMEROUS STRONG CONVECTIVE PRECIPITATION IS FROM 8N TO 12N BETWEEN 31W AND 34W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND OTHER POSSIBLE RAINSHOWERS ARE ELSEWHERE FROM 8N TO 18N BETWEEN 23W AND 36W. A MIDDLE LEVEL TO UPPER LEVEL INVERTED TROUGH IS ALONG 23N31W 17N34W 10N35W TO THE WEST OF THIS WAVE. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD 15 TO 20 MPH. A SURFACE TROUGH IS ALONG 25N96W IN THE NORTHEASTERN MEXICO COASTAL WATERS TO THE MEXICO COASTAL PLAINS NEAR 20N97W. SCATTERED TO NUMEROUS STRONG CONVECTIVE PRECIPITATION IS FROM 20N TO 24N BETWEEN 96W AND 97.5W. SOME GRADUAL DEVELOPMENT OF THIS SYSTEM STILL IS POSSIBLE IF IT REMAINS OVER WATER DURING THE NEXT DAY OR TWO. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT DRIFTS WESTWARD. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 60W FROM 10N TO 18N. SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS FROM 15N TO 16N BETWEEN 61W AND 62W IN THE EASTERN CARIBBEAN SEA ISLANDS. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED RAINSHOWERS COVER THE ATLANTIC OCEAN AND THE CARIBBEAN SEA ELSEWHERE FROM TO THE SOUTH OF 19N BETWEEN 58W AND 65W. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 85W/86W... REACHING EAST CENTRAL HONDURAS AND NORTHWESTERN NICARAGUA. AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 18N90W IN NORTHERN GUATEMALA. UPPER LEVEL CYCLONIC WIND FLOW MOVES AROUND THE 18N90W CIRCULATION CENTER FROM EL SALVADOR AND HONDURAS TO THE YUCATAN CHANNEL AND THE YUCATAN PENINSULA OF MEXICO BETWEEN 85W AND 95W IN THE ISTHMUS OF TEHUANTEPEC OF MEXICO. CONVECTIVE PRECIPITATION...SCATTERED STRONG IN THE GULF OF HONDURAS AND SOUTHERN BELIZE...SCATTERED MODERATE TO ISOLATED STRONG IN THE CARIBBEAN SEA TO THE NORTH OF 12N TO THE WEST OF 80W. THE NUMEROUS STRONG PRECIPITATION THAT COVERED THE ISTHMUS OF TEHUANTEPEC SIX HOURS EARLIER HAS WEAKENED AND DISSIPATED. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL MAURITANIA NEAR 18N16W TO 15N20W...TO THE 1010 MB LOW PRESSURE CENTER THAT IS NEAR 10N29W...TO 9N36W AND 9N46W. THE MONSOON TROUGH IS BROKEN UP BY THE CIRCULATION THAT IS MOVING AROUND T.D. NINE. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE TO THE SOUTH OF 10N TO THE WEST OF 23...ISOLATED MODERATE FROM 9N TO 11N BETWEEN AFRICA AND 18W. ...DISCUSSION... THE GULF OF MEXICO... PLEASE READ THE SPECIAL FEATURES SECTION REFERRING TO THE 25N96W 20N97W SURFACE TROUGH THAT RUNS FROM THE NORTHEASTERN MEXICO COASTAL WATERS TO THE MEXICO COASTAL PLAINS. PLEASE READ THE TROPICAL WAVES SECTION FOR MORE DETAILS ABOUT THE WESTERN CARIBBEAN SEA TROPICAL WAVE THAT IS ALONG 85W/86W. MIDDLE LEVEL TO UPPER LEVEL CYCLONIC WIND FLOW COVERS THE AREA TO THE NORTHWEST OF THE LINE FROM MEXICO NEAR 21N97W TO 25N88W BEYOND 32N76W IN THE ATLANTIC OCEAN. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED MODERATE CONVECTIVE PRECIPITATION ARE TO THE SOUTHEAST OF THE LINE THAT RUNS FROM THE FLORIDA PANHANDLE ALONG 87W TO THE COASTAL BORDER OF TEXAS AND MEXICO. THE SURFACE PRESSURE GRADIENT IS COMPARATIVELY WEAK AT THE MOMENT. A SURFACE RIDGE PASSES THROUGH A 1022 MB HIGH PRESSURE CENTER THAT IS NEAR 28N61W...TO SOUTHEASTERN FLORIDA...INTO THE TO 21N84W IN THE NORTHWESTERN CARIBBEAN SEA. FROM THE EAST CENTRAL ATLANTIC OCEAN...INTO THE NORTH CENTRAL AND SOUTH CENTRAL CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 33N34W TO A 30N41W CYCLONIC CIRCULATION CENTER...TO 24N41W AND 27N51W. A SHEAR AXIS CONTINUES FROM 27N51W TO 30N57W. A TROUGH CONTINUES FROM 30N57W TO A 25N60W CYCLONIC CIRCULATION CENTER. THE TROUGH CONTINUES FROM 25N60W TO A 22N69W CYCLONIC CIRCULATION CENTER... CROSSING HISPANIOLA AND REACHING 15N72W IN THE CARIBBEAN SEA...TO 13N73W. CONVECTIVE PRECIPITATION IN THE ATLANTIC OCEAN...ISOLATED MODERATE ELSEWHERE TO THE NORTH OF 20N BETWEEN 58W AND 70W...SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE FROM THE BAHAMAS NEAR 26N NORTHWARD BETWEEN 70W AND 80W IN AN AREA OF SOME UPPER LEVEL DIFFLUENT WIND FLOW. AN ATLANTIC OCEAN SURFACE TROUGH PASSES THROUGH 32N30W TO 27N40W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION TO THE NORTH OF 26N BETWEEN 30W AND 41W. THE REST OF THE CARIBBEAN SEA... PLEASE READ THE TROPICAL WAVES SECTION FOR MORE DETAILS ABOUT THE WESTERN CARIBBEAN SEA TROPICAL WAVE THAT IS ALONG 20N84W... REACHING EASTERN COASTAL HONDURAS NEAR 16N85W...INTO CENTRAL NICARAGUA NEAR 13N85W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 60W FROM 10N TO 18N. SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS FROM 15N TO 16N BETWEEN 61W AND 62W IN THE EASTERN CARIBBEAN SEA ISLANDS. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED RAINSHOWERS COVER THE ATLANTIC OCEAN AND THE CARIBBEAN SEA ELSEWHERE FROM TO THE SOUTH OF 19N BETWEEN 58W AND 65W. OTHER BROKEN LOW TO MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS ARE BETWEEN 65W AND 73W...WELL TO THE WEST OF THE ADVANCING TROPICAL WAVE. THE MONSOON TROUGH IS ALONG 7N/8N BETWEEN 73W IN COLOMBIA...BEYOND 83W COSTA RICA. NUMEROUS STRONG CONVECTIVE PRECIPITATION IS IN COLOMBIA FROM 8N TO 9N BETWEEN 73W AND 76W. SCATTERED STRONG CONVECTIVE PRECIPITATION IS WITHIN 30 NM ON EITHER SIDE OF 12N80W 10N77W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT T.D. NINE AND ITS CONTINUED INTENSIFICATION. A SECOND AREA IS FROM 11N TO 18N BETWEEN 68W AND 80W FOR 20 TO 25 KNOT WINDS AND 8 TO 9 FOOT SEA HEIGHTS. A THIRD AREA IS TO THE SOUTH OF 19N TO THE WEST OF 84W INCLUDING IN THE GULF OF HONDURAS FOR 20 TO 25 KNOT WINDS AND 8 FOOT SEA HEIGHTS. THE REST OF THE ATLANTIC OCEAN... A SURFACE RIDGE PASSES THROUGH 32N33W TO A 1021 MB HIGH PRESSURE CENTER THAT IS NEAR 33N49W...TO A 1022 MB HIGH PRESSURE CENTER THAT IS NEAR 28N61W...TO 27N71W...ACROSS THE CENTRAL BAHAMAS... INTO THE NORTHWESTERN CARIBBEAN SEA NEAR 21N84W. PLEASE READ THE HIGH SEAS FORECASTS...MIAHSFAT2...FOR DETAILS ABOUT T.D. NINE...AND THE 1009 MB LOW PRESSURE CENTER THAT IS NEAR 11N34W...POSSIBLY DEVELOPING INTO A TROPICAL CYCLONE NEAR 12.5N37W IN 48 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT