000 AXNT20 KNHC 250004 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU AUG 22 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... A GULF OF MEXICO TROPICAL WAVE IS ALONG 25N89W...CUTTING ACROSS THE NORTHWESTERN CORNER OF THE YUCATAN PENINSULA OF MEXICO...TO A 1009 MB LOW PRESSURE CENTER THAT IS IN THE NORTHWESTERN CORNER OF GUATEMALA...THROUGH THE REST OF GUATEMALA...TO 11N92W IN THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED STRONG WITHIN 30 NM ON EITHER SIDE OF 23N86W 21N90W 19N91W...IN THE ISTHMUS OF TEHUANTEPEC OF SOUTHERN MEXICO BETWEEN 93W AND 95W...IN SOUTHEASTERN GUATEMALA...AND ALONG THE EASTERN PACIFIC OCEAN COAST OF GUATEMALA IN THE SOUTHWESTERN PART OF THE COUNTRY. THE 24-HOUR RAINFALL TOTALS IN INCHES AS OF 24/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLE...MIATPTPAN...ARE 2.17 IN TEGUCIGALPA HONDURAS...AND 1.21 IN MERIDA MEXICO. THIS DISTURBANCE IS FORECAST TO MOVE TOWARD THE WEST-NORTHWEST TONIGHT AND SUNDAY ACROSS THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...WHERE WHERE ENVIRONMENTAL CONDITIONS APPEAR TO BE FAVORABLE FOR SOME DEVELOPMENT. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. AN AIR FORCE PLANE IS SCHEDULED TO INVESTIGATE THE SYSTEM ON SUNDAY AFTERNOON...IF NECESSARY. IT IS LIKELY THAT THIS DISTURBANCE IS WILL MOVE INLAND OVER THE STATE OF VERACRUZ MEXICO IN A COUPLE OF DAYS...WHETHER OR NOT A TROPICAL CYCLONE FORMS. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 29W/30W TO THE SOUTH OF 20N MOVING WESTWARD 15 KNOTS. CONVECTIVE PRECIPITATION... SCATTERED STRONG FROM 8N TO 9N BETWEEN 30W AND 31W. ISOLATED MODERATE ELSEWHERE FROM 7N TO 13N BETWEEN 28W AND 35W. A SURFACE TROUGH IS ALONG 15N43W...TO A 1010 MB LOW PRESSURE CENTER THAT IS NEAR 13N43W...TO 10N45W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 11N TO 13N BETWEEN 43W AND 46W. AN ATLANTIC OCEAN SURFACE TROUGH IS ALONG 53W/54W TO THE SOUTH OF 23N. CONVECTIVE PRECIPITATION...ISOLATED MODERATE FROM 14N TO 25N BETWEEN 49W AND 58W. AN ATLANTIC OCEAN-TO-CARIBBEAN SEA TROPICAL WAVE IS ALONG 20N60W...PASSING ACROSS GUADELOUPE...TO THE VENEZUELA COAST NEAR 10N62W. THE WAVE IS MOVING WESTWARD 15 KNOTS. SCATTERED STRONG FROM 14N TO 15N BETWEEN 60W AND 62W...AND FROM 15N TO 16N BETWEEN 65W AND 67W. RAINSHOWERS ARE POSSIBLE ELSEWHERE TO THE SOUTH OF 18N BETWEEN 59W AND 70W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SENEGAL NEAR 16N17W TO 16N20W 12N30W 11N35W AND 10N41W. CONVECTIVE PRECIPITATION... NUMEROUS STRONG FROM 10N TO 15N BETWEEN 13W AND 17W...COVERING INTERIOR SECTIONS AND COASTAL SECTIONS OF AFRICA FROM GUINEA TO SENEGAL. SCATTERED STRONG FROM 7N TO 8N BETWEEN 9W IN LIBERIA AND 15W IN THE ATLANTIC OCEAN. SCATTERED STRONG FROM 11N TO 12N BETWEEN 37W AND 39W...FROM 12N TO 13N BETWEEN 35W AND 37W. SCATTERED MODERATE TO ISOLATED STRONG WITHIN 30 NM ON EITHER SIDE OF 9N BETWEEN 41W AND 42W. RAINSHOWERS ARE POSSIBLE TO THE SOUTH OF 11N TO THE WEST OF 47W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE LEVEL CYCLONIC CIRCULATION CENTER IS IN THE COASTAL WATERS OF SOUTHWESTERN LOUISIANA. A SURFACE TROUGH IS ALONG 28N84W 29N90W 26N94W IN THE NORTHERN GULF OF MEXICO. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 25N TO 30N BETWEEN 85W AND 92W. A TROUGH IS IN THE GULF OF MEXICO ALONG 94W/95W FROM THE MEXICO COAST TO 26N. A MIDDLE LEVEL TO UPPER CYCLONIC CIRCULATION CENTER IS IN NEAR 23N95W. A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ON TOP OF MEXICO ALONG 28N102W 24N101W 21N101W. CONVECTIVE PRECIPITATION...ISOLATED TO WIDELY SCATTERED MODERATE ELSEWHERE TO THE SOUTH OF 27N TO THE WEST OF 92W. AN UPPER LEVEL RIDGE IS ALONG 31N84W IN SOUTHERN GEORGIA... 26N84W...TO THE NORTHEASTERN CORNER OF THE YUCATAN PENINSULA OF MEXICO. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IN FLORIDA TO THE SOUTH AND SOUTHWEST OF LAKE OKEECHOBEE...AND FROM 28N TO 29N. MULTILAYERED CLOUD CEILINGS COVER SOUTHERN COASTAL LOUISIANA. RAIN IS REPORTED FROM NEW IBERIA TOWARD THE SOUTHEAST. MIDDLE LEVEL AND HIGH LEVEL CLOUD CEILINGS COVER THE AREA THAT IS IMMEDIATELY TO THE SOUTH OF LAKE PONTCHARTRAIN. A MIDDLE LEVEL AND A HIGH CLOUD CEILING ARE OBSERVED IN VALPARAISO FLORIDA. LIGHT RAIN IS OBSERVED IN MARIANNA FLORIDA. MULTILAYERED CLOUD CEILINGS AND RAINSHOWERS WITH THUNDER COVER THE FLORIDA WEST COAST FROM NAPLES TO TAMPA. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE ACROSS THE AREA. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... LOW CLOUD CEILINGS ARE AT THE ICAO STATIONS KEIR AND KSPR. MIDDLE LEVEL CLOUD CEILINGS ARE AT THE ICAO STATIONS KGBK AND KVAF. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE ACROSS THE AREA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT4...FOR MORE DETAILS ABOUT THE 12 HOUR FORECAST OF EAST TO SOUTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 FEET WITHIN 180 NM IN THE NORTHEASTERN QUADRANT WITH A 1009 MB LOW PRESSURE CENTER NEAR 19N93.5W. THE CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 24N68W IN THE ATLANTIC OCEAN...TO A CYCLONIC CIRCULATION CENTER THAT IS ON TOP OF THE BORDER OF HAITI AND THE DOMINICAN REPUBLIC...INTO THE CARIBBEAN SEA TO 16N75W...TO 9N76W ALONG THE COAST OF COLOMBIA. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO STRONG FROM THE WESTERN SECTIONS OF THE DOMINICAN REPUBLIC DIRECTLY INTO HAITI. SCATTERED TO NUMEROUS STRONG IN CUBA AND ITS COASTAL WATERS FROM 19N77W BETWEEN JAMAICA AND CUBA...NORTHWESTWARD ALONG THE CARIBBEAN SEA COAST OF CUBA TO 83W IN CUBA. AN ATLANTIC OCEAN-TO-CARIBBEAN SEA TROPICAL WAVE IS ALONG 20N60W...PASSING ACROSS GUADELOUPE...TO THE VENEZUELA COAST NEAR 10N62W. THE WAVE IS MOVING WESTWARD 15 KNOTS. SCATTERED STRONG FROM 14N TO 15N BETWEEN 60W AND 62W...AND FROM 15N TO 16N BETWEEN 65W AND 67W. RAINSHOWERS ARE POSSIBLE ELSEWHERE TO THE SOUTH OF 18N BETWEEN 59W AND 70W. THE 24-HOUR RAINFALL TOTAL IN INCHES AS OF 22/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLE...MIATPTPAN...IS 0.19 IN ST. THOMAS. THE MONSOON TROUGH IS ALONG 9N/10N BETWEEN 74W IN COLOMBIA BEYOND 86W IN THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IN COLOMBIA FROM 10N TO 11N BETWEEN 74W AND 75W...FROM 7N IN COLOMBIA TO 9N IN PANAMA BETWEEN 77W AND 79W...AND FROM SOUTHERN COSTA RICA TO CENTRAL AND NORTHWESTERN NICARAGUA. ISOLATED TO WIDELY SCATTERED MODERATE ELSEWHERE IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO THE SOUTH OF 13N TO THE WEST OF 76W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT THE EAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS FROM 8 TO 10 FEET FROM 11.5N TO 16N BETWEEN 72W AND 81W. EXPECT ALSO EAST TO SOUTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS LOWER THAN 8 FEET TO THE SOUTH OF 20N TO THE WEST OF 83W INCLUDING IN THE GULF OF HONDURAS. HISPANIOLA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 24N68W IN THE ATLANTIC OCEAN...TO A CYCLONIC CIRCULATION CENTER THAT IS ON TOP OF THE BORDER OF HAITI AND THE DOMINICAN REPUBLIC...INTO THE CARIBBEAN SEA TO 16N75W...TO 9N76W ALONG THE COAST OF COLOMBIA. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO STRONG FROM THE WESTERN SECTIONS OF THE DOMINICAN REPUBLIC DIRECTLY INTO HAITI. SCATTERED TO NUMEROUS STRONG IN CUBA AND ITS COASTAL WATERS FROM 19N77W BETWEEN JAMAICA AND CUBA...NORTHWESTWARD ALONG THE CARIBBEAN SEA COAST OF CUBA TO 83W IN CUBA. THE 700 MB GFS FORECAST SHOWS THAT BROAD EASTERLY WIND FLOW WILL PREVAIL FOR THE ENTIRE 48 HOUR PERIOD. THE 500 MB GFS MODEL SHOWS THAT AN INVERTED TROUGH WILL CUT ACROSS THE AREA FOR THE FIRST 24 HOURS...TO BE REPLACED BY A RIDGE FOR THE REST OF THE 48 HOUR PERIOD. THE 250 MB GFS FORECAST SHOWS THAT A TROUGH WILL COVER THE AREA FOR MOST OF THE FIRST 24 HOURS...BEING REPLACED BY LARGE SCALE ANTICYCLONIC WIND FLOW. THE ATLANTIC OCEAN... A SURFACE RIDGE PASSES THROUGH 32N43W TO 28N58W 27N72W...ACROSS THE NORTHERN BAHAMAS TO THE FLORIDA COAST NEAR 26N. SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN TO THE NORTH OF 24N TO THE EAST OF FLORIDA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR DETAILS ABOUT THE NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 FEET FROM 21N TO 25N TO THE EAST OF 38W FOR THE NEXT 6 HOURS OR SO. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT