000 AXNT20 KNHC 201805 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED AUG 20 2014 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 1745 UTC. ...SPECIAL FEATURES... A 1009 MB ATLANTIC OCEAN LOW PRESSURE CENTER IS NEAR 11N53W...IN THE MONSOON TROUGH. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 10N TO 13N BETWEEN 50W AND 52W...AND FROM 10N TO 12N BETWEEN 53W AND 57W. SCATTERED STRONG ALSO IS FROM 8N TO 10N BETWEEN 55W AND 60W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 8N TO 10N BETWEEN 50W AND 55W. GRADUAL DEVELOPMENT OF THIS FEATURE IS POSSIBLE DURING THE NEXT FEW DAYS...WHILE IT WILL BE MOVING WESTWARD-NORTHWESTWARD 10 TO 15 KNOTS...ACROSS THE LESSER ANTILLES INTO THE CARIBBEAN SEA. PEOPLE WHO LIVE IN THE LESSER ANTILLES AND THE ISLANDS OF THE NORTHEASTERN CARIBBEAN SEA SHOULD MONITOR CLOSELY THE PROGRESS OF THIS FEATURE. THE CHANCE FOR DEVELOPMENT INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS IS MEDIUM. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 23W FROM 22N SOUTHWARD. THE WAVE IS MOVING WESTWARD 20 KNOTS. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG IS THE PRECIPITATION THAT IS THE CLOSEST TO THE WAVE...FROM 7N TO 15N BETWEEN 25W AND 34W AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 24N50W 19N49W 14N48W 10N48W...MOVING WESTWARD 15 TO 20 KNOTS. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 15N TO 17N BETWEEN 49W AND 50W. OTHER NEARBY PRECIPITATION IS CLOSER TO THE SPECIAL FEATURE 1009 MB LOW PRESSURE CENTER THAT IS NEAR 11N53W. AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 62W FROM 22N SOUTHWARD TO NORTHEASTERN VENEZUELA...MOVING WESTWARD 20 KNOTS. CONVECTIVE PRECIPITATION...NO OTHER SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT AT THIS MOMENT. THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 20/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...WAS 0.92 IN TRINIDAD. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL BORDER SECTIONS OF SENEGAL...NEAR 18N16W...TO 14N26W 14N40W...TO THE 11N53W SPECIAL FEATURE LOW PRESSURE CENTER...TO 8N57W. NO OTHER SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT AT THIS MOMENT. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS ALONG THE COAST OF MEXICO NEAR 23N98W. CYCLONIC WIND FLOW THAT IS MOVING AROUND THE 23N98W CENTER COVERS THE AREA THAT GOES FROM 19N IN MEXICO TO 28N ALONG THE TEXAS COAST BETWEEN 93W AND 103W. CONVECTIVE PRECIPITATION...ISOLATED MODERATE IN THE GULF OF MEXICO FROM 25N NORTHWARD FROM 90W WESTWARD. A WESTERN ATLANTIC OCEAN MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG THE SOUTHEASTERN COAST OF THE U.S.A. FROM THE COASTAL WATERS OF SOUTH CAROLINA TO THE GEORGIA COASTAL WATERS TO EAST CENTRAL FLORIDA. A SURFACE TROUGH IS ALONG 33N76W TO 27N81W ALONG THE FLORIDA EAST COAST. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE AREA THAT GOES FROM THE BAHAMAS TO THE FLORIDA STRAITS...AND SOUTH FLORIDA FROM THE ATLANTIC OCEAN SIDE TO THE GULF OF MEXICO SIDE...FROM 90W EASTWARD. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG IN THE WATERS THAT ARE BETWEEN THE BAHAMAS AND THE FLORIDA STRAITS...AND FROM 24N TO 26N BETWEEN FLORIDA AND 88W. ISOLATED MODERATE IN THE NORTHEASTERN CORNER OF THE GULF OF MEXICO. A SURFACE RIDGE PASSES FROM THE ATLANTIC OCEAN...THROUGH 28N63W...ACROSS THE BAHAMAS AND SOUTH FLORIDA...TO A 1018 MB GULF OF MEXICO HIGH PRESSURE CENTER THAT IS NEAR 27N87W...ACROSS THE GULF OF MEXICO TO THE TEXAS/MEXICO COASTAL BORDER. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... NO LOW LEVEL CLOUD CEILINGS ARE BEING REPORTED AT THE SITES. FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... IN TEXAS...MULTILAYERED CLOUD CEILINGS ARE IN THE CORPUS CHRISTI AREA. LOW LEVEL CLOUD CEILINGS ARE BEING REPORTED AND/OR HAVE BEEN REPORTED DURING THE LAST FEW OBSERVATIONS IN AREAS THAT ARE TO THE NORTH AND NORTHWEST OF THE HOUSTON INTERCONTINENTAL AIRPORT...AND IN BEAUMONT-PORT ARTHUR. IN LOUISIANA...A LOW LEVEL CLOUD CEILING IS BEING REPORTED IN THE LAKE CHARLES METROPOLITAN AREA. MULTILAYERED CLOUD CEILINGS ARE BEING REPORTED AROUND LAKE PONTCHARTRAIN IN SOUTHEASTERN LOUISIANA. IN ALABAMA...A LOW LEVEL CLOUD CEILING IS BEING REPORTED IN GULF SHORES. IN FLORIDA...MULTILAYERED CLOUD CEILINGS ARE BEING REPORTED IN THE FORT MYERS METROPOLITAN AREA. RAINSHOWERS WITH THUNDER ARE BEING OBSERVED AT THE KEY WEST INTERNATIONAL AIRPORT. A LOW CLOUD CEILING IS BEING OBSERVED AT THE NAVAL AIR STATION IN KEY WEST. A LOW CLOUD CEILING IS BEING OBSERVED IN NAPLES. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT4/FZNT24 KNHC...FOR MORE DETAILS ABOUT...THE GULF OF MEXICO 12 HOUR FORECAST ALONG YUCATAN PENINSULA FROM 19N TO 22N BETWEEN 89W AND 92W NE TO E WINDS 20 TO 25 KT. SEAS LESS THAN 8 FT. FROM THE ATLANTIC OCEAN INTO THE CARIBBEAN SEA...ACROSS PUERTO RICO AND HISPANIOLA...INCLUDING THE REST OF HISPANIOLA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM 30N60W IN THE ATLANTIC OCEAN...TO AN ATLANTIC OCEAN CYCLONIC CIRCULATION CENTER THAT IS NEAR 22N64W...ACROSS PUERTO RICO...TO 15N67W IN THE CARIBBEAN SEA. CYCLONIC WIND FLOW THAT IS MOVING AROUND THE TROUGH COVERS THE ATLANTIC OCEAN FROM 31N SOUTHWARD BETWEEN 53W AND 80W...AND IN THE CARIBBEAN SEA FROM 16N NORTHWARD BETWEEN 60W AND THE WINDWARD PASSAGE. CONVECTIVE PRECIPITATION... SCATTERED MODERATE TO ISOLATED STRONG IN THE CARIBBEAN SEA FROM 16N TO 20N BETWEEN 65W AND THE WINDWARD PASSAGE. ISOLATED MODERATE IN THE ATLANTIC OCEAN IN GENERAL FROM 20N NORTHWARD BETWEEN 55W AND 80W...AND SPECIFICALLY FROM 23N TO 28N BETWEEN 62W AND 68W. CLOUD CONDITIONS...FOR THE DOMINICAN REPUBLIC...FEW CUMULONIMBUS CLOUDS...AND FEW LOW LEVEL CLOUDS COVER BARAHONA. RAINSHOWERS ARE BEING OBSERVED IN SANTO DOMINGO. FEW LOW LEVEL CLOUDS ARE IN LA ROMANA. FEW CUMULONIMBUS CLOUDS...OTHER SCATTERED LOW LEVEL CLOUDS...AND SCATTERED MIDDLE LEVEL CLOUDS ARE BEING REPORTED IN PUNTA CANA. FEW TO SCATTERED LOW LEVEL CLOUDS AND SCATTERED HIGH LEVEL CLOUDS ARE FOUND FROM SANTIAGO TO PUERTO PLATA. THE GFS MODEL FORECAST FOR 250 MB SHOWS THAT CYCLONIC WIND FLOW...FROM THE CURRENT MIDDLE LEVEL TO UPPER LEVEL TROUGH... WILL COVER HISPANIOLA FOR THE FIRST 24 HOURS OF THE 48 HOUR FORECAST PERIOD. AN INVERTED TROUGH WILL DEVELOP ACROSS THE AREA AT 24 HOURS...AND IT WILL REMAIN FOR THE REST OF THE FORECAST PERIOD. THE GFS MODEL FOR 500 MB SHOWS THAT FIRST NORTHEAST TO EAST WIND FLOW WILL COVER THE AREA. THE GFS MODEL FOR 700 MB SHOWS THAT EAST TO SOUTHEAST WIND FLOW WILL CROSS HISPANIOLA...WITH AN ATLANTIC OCEAN RIDGE. THE CARIBBEAN SEA... AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 62W FROM 22N SOUTHWARD TO NORTHEASTERN VENEZUELA...MOVING WESTWARD 20 KNOTS. CONVECTIVE PRECIPITATION...NO OTHER SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT AT THIS MOMENT. THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 20/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...WAS 0.92 IN TRINIDAD. UPPER LEVEL WESTERLY-TO-NORTHWESTERLY WIND FLOW IS IN SOUTHERN SECTIONS OF THE CARIBBEAN SEA...FROM 17N SOUTHWARD BETWEEN THE COAST OF CENTRAL AMERICA TO NORTHWESTERN COASTAL VENEZUELA. MIDDLE LEVEL TO UPPER LEVEL EAST-TO-SOUTHEAST WIND FLOW ALSO COVERS THE AREA THAT GOES FROM THE WINDWARD PASSAGE WESTWARD. THE SURFACE PRESSURE GRADIENT IS COMPARATIVELY WEAK ACROSS THE AREA. CONVECTIVE PRECIPITATION...THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 20/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...WAS 0.92 IN TRINIDAD... 0.51 IN SAN JUAN IN PUERTO RICO...AND 0.12 IN CURACAO. THE MONSOON TROUGH IS ALONG 8N/9N BETWEEN 75W IN NORTHERN COLOMBIA...AND BEYOND 86W...INTO THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO STRONG FROM 13N SOUTHWARD FROM 78W WESTWARD...IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...FOR MORE DETAILS ABOUT...ATLC AND CARIBBEAN LOW PRES NEAR 11N53W 1009 MB MOVING NW 10 KT WITH TROUGH NE TO 13N50W. WITHIN 60 NM OF LOW WINDS 20 TO 25 KT. SEAS TO 8 FT. WITHIN 120 NM S OF TROUGH S TO SW WINDS 20 TO 25 KT. SEAS TO 8 FT. SCATTERED TSTMS WITHIN 120 NM OF LOW...AND WITHIN 90 OF TROUGH. CARIBBEAN SEA FROM 11N TO 14N BETWEEN 72W AND 76W NE TO E WINDS 20 TO 25 KT. SEAS TO 8 FT. CARIBBEAN SEA 12 HOUR FORECAST S OF 17N W OF 85W...INCLUDING THE GULF OF HONDURAS...E WINDS 20 TO 25 KT. SEAS LESS THAN 8 FT. THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC CIRCULATION CENTER IS NEAR 32N46W. THE ANTICYCLONIC CENTER IS SURROUNDED BY COMPARATIVELY DRIER AIR IN SUBSIDENCE...APPARENT IN WATER VAPOR IMAGERY. A MIDDLE LEVEL TO UPPER LEVEL INVERTED TROUGH IS ALONG 30W FROM 20N NORTHWARD. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT AT THIS MOMENT. A SURFACE RIDGE EXTENDS FROM A 1023 MB HIGH PRESSURE CENTER THAT IS NEAR 32N46W. A SURFACE RIDGE PASSES FROM THE ATLANTIC OCEAN...THROUGH 28N63W...ACROSS THE BAHAMAS AND SOUTH FLORIDA...TO A 1018 MB GULF OF MEXICO HIGH PRESSURE CENTER THAT IS NEAR 27N87W...ACROSS THE GULF OF MEXICO TO THE TEXAS/MEXICO COASTAL BORDER. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...FOR MORE DETAILS ABOUT...LOW PRES NEAR 11N53W 1009 MB MOVING NW 10 KT WITH TROUGH NE TO 13N50W. WITHIN 60 NM OF LOW WINDS 20 TO 25 KT. SEAS TO 8 FT. WITHIN 120 NM S OF TROUGH S TO SW WINDS 20 TO 25 KT. SEAS TO 8 FT. SCATTERED TSTMS WITHIN 120 NM OF LOW...AND WITHIN 90 OF TROUGH. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT