000 AXNT20 KNHC 211108 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI AUG 21 2015 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 1045 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE DANNY AT 21/0900 UTC IS NEAR 13.7N 47.4W...OR 840 NM TO THE EAST OF THE WINDWARD ISLANDS...MOVING WEST-NORTHWESTWARD...OR 290 DEGREES...09 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 987 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 75 KNOTS WITH GUSTS TO 90 KNOTS. CONVECTIVE PRECIPITATION...NUMEROUS STRONG WITHIN A RADIUS OF 60 NM OF THE CENTER IN THE EASTERN SEMICIRCLE...AND WITHIN A RADIUS OF 30 NM TO 60 NM OF THE CENTER IN THE WESTERN SEMICIRCLE. ISOLATED MODERATE ELSEWHERE WITHIN A RADIUS OF 285 NM OF THE CENTER IN THE EASTERN SEMICIRCLE...AND ELSEWHERE WITHIN A RADIUS OF 180 NM OF THE CENTER IN THE WESTERN SEMICIRCLE. PUBLIC ADVISORIES ABOUT HURRICANE DANNY ARE BEING ISSUED UNDER WMO HEADER WTNT34 KNHC AND UNDER AWIPS HEADER MIATCPAT4. FORECAST/ADVISORIES ABOUT HURRICANE DANNY ARE BEING ISSUED UNDER WMO HEADER WTNT24 KNHC AND UNDER AWIPS HEADER MIATCMAT4. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 22N28W 15N30W 06N30W... MOVING WESTWARD 10 KNOTS. CONVECTIVE PRECIPITATION...RAINSHOWERS ARE POSSIBLE WITHIN 60 NM ON EITHER SIDE OF THE WAVE. A CARIBBEAN SEA TROPICAL WAVE IS ALONG THE LINE FROM 19N67W...THROUGH THE MONA PASSAGE...TO 15N68W...TO 10N68W IN VENEZUELA. THE WAVE IS MOVING WESTWARD 10 TO 15 KNOTS. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG WITHIN A 15 NM TO 30 NM RADIUS OF 16.5N61W NEAR LA DESIRADE/ GUADELOUPE IN THE LEEWARD ISLANDS. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 20N SOUTHWARD BETWEEN 60W AND 74W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF SENEGAL NEAR 14N17W TO 10N22W 08N30W AND 10N38W. NO ITCZ IS PRESENT AT THIS MOMENT. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 05N TO 16N FROM 30W EASTWARD... FROM 07N TO 10N BETWEEN 40W AND 50W...AND FROM 11N SOUTHWARD BETWEEN 50W AND 60W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG 99W/100W IN MEXICO. MOST OF THE CYCLONIC WIND FLOW THAT IS MOVING AROUND THE TROUGH IS INLAND. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IS IN THE COASTAL PLAINS/COASTAL WATERS OF SOUTH TEXAS AND EXTREME NORTHEASTERN MEXICO. SCATTERED MODERATE TO ISOLATED STRONG IS IN THE COASTAL PLAINS/COASTAL WATERS OF MEXICO FROM 18N TO 24N. THE UPPER LEVEL ANTICYCLONIC WIND FLOW THAT WAS COVERING THE ENTIRE GULF OF MEXICO 24 HOURS AGO...NOW...MOSTLY COVERS THE GULF OF MEXICO JUST FROM 25N NORTHWARD. COVERING THE SOUTHEASTERN CORNER OF THE GULF OF MEXICO...AND THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA... THE SOUTHEASTERN CORNER OF THE GULF OF MEXICO IS BEING INVADED BY A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER THAT IS NEAR 18N89W IN BELIZE. CYCLONIC WIND FLOW COVERS THE AREA FROM HONDURAS NEAR 13N TO 24N IN THE GULF OF MEXICO... BETWEEN 80W AND 94W IN THE GULF OF MEXICO. CONVECTIVE PRECIPITATION...ISOLATED MODERATE TO LOCALLY STRONG IN THE COASTAL WATERS AND COASTAL PLAINS OF CUBA ON THE CARIBBEAN SEA SIDE. BROKEN TO OVERCAST MULTILAYERED CONVECTIVE DEBRIS CLOUDS REMAIN FROM 15N NORTHWARD FROM 81W WESTWARD. THE REST OF THE CARIBBEAN SEA... A SURFACE TROUGH EXTENDS FROM A 1008 MB LOW PRESSURE CENTER THAT IS NEAR 10N74W IN COLOMBIA...TO 05N77W ALONG THE EASTERN PACIFIC OCEAN COAST OF COLOMBIA...AND TO 03N81W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IN COLOMBIA FROM 07N TO 10N BETWEEN 75W AND 78W...AND IN COASTAL AREAS OF COLOMBIA AND PANAMA FROM 02N TO 08N BETWEEN 76W AND 81W. OTHER SCATTERED MODERATE TO ISOLATED STRONG PRECIPITATION IS IN LAKE MARACAIBO IN NORTHWESTERN VENEZUELA. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE CARIBBEAN SEA FROM 17N SOUTHWARD FROM 80W EASTWARD. ...HISPANIOLA... OBSERVATIONS...IN HAITI...THE EARLIER NUMEROUS STRONG CONVECTIVE PRECIPITATION FOR PORT-AU-PRINCE HAS ENDED. SCATTERED LOW LEVEL CLOUDS AND A MIDDLE LEVEL CLOUD CEILING REMAIN. FOR THE DOMINICAN REPUBLIC...FEW LOW LEVEL CLOUDS AND SCATTERED HIGH LEVEL CLOUDS ARE IN SANTO DOMINGO. FEW LOW LEVEL CLOUDS ARE IN PUNTA CANA. FEW CUMULONIMBUS CLOUDS AND A MIDDLE LEVEL CLOUD CEILING ARE BEING OBSERVED IN SANTIAGO. FEW LOW LEVEL CLOUDS ARE IN PUERTO PLATA. THE GFS MODEL FORECAST FOR 250 MB SHOWS THAT NORTHERLY WIND FLOW WILL MOVE ACROSS THE AREA WITH A NORTHEAST-TO-SOUTHWEST ORIENTED TROUGH. THE GFS MODEL FORECAST FOR 500 MB SHOWS THAT NORTHEAST WIND FLOW WILL PASS ACROSS THE AREA FOR THE FIRST 24 HOURS. INVERTED TROUGHS WILL PASS THROUGH THE AREA FROM 24 HOURS UNTIL 48 HOURS. THE GFS MODEL FORECAST FOR 700 MB SHOWS THAT NORTHEASTERLY WIND FLOW WILL MOVE ACROSS THE AREA. THE ATLANTIC OCEAN... HURRICANE DANNY IS IN THE ATLANTIC OCEAN. PLEASE READ THE SPECIAL FEATURES SECTION FOR MORE DETAILS ABOUT THE HURRICANE. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 34N65W. A SECOND MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 33N46W. CYCLONIC WIND FLOW COVERS THE AREA THAT IS TO THE NORTHWEST OF THE LINE 30N18W 24N40W 22N60W 22N66W 24N72W 30N80W. A 1012 MB LOW PRESSURE CENTER IS NEAR 30N66W. A SURFACE TROUGH EXTENDS FROM THE LOW CENTER TO 27N61W. A SECOND SURFACE TROUGH EXTENDS FROM THE LOW CENTER TO 27N69W AND 28N74W. A 1016 MB LOW PRESSURE CENTER IS NEAR 29N44W. ONE SURFACE TROUGH EXTENDS FROM THE LOW CENTER BEYOND 32N44W. A SECOND SURFACE TROUGH EXTENDS FROM THE LOW CENTER TO 26N46W AND 26N49W. CONVECTIVE PRECIPITATION...WIDELY SCATTERED TO SCATTERED MODERATE AND ISOLATED STRONG FROM 24N NORTHWARD BETWEEN 54W AND 81W. WIDELY SCATTERED TO SCATTERED MODERATE AND ISOLATED STRONG FROM 30N BETWEEN 38W AND 43W. ISOLATED MODERATE ELSEWHERE FROM 25N NORTHWARD BETWEEN 38W AND 52W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT