000 AXNT20 KNHC 210604 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT SEP 21 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 20W/21W TO THE SOUTH OF 18N MOVING WESTWARD 10 TO 15 KNOTS. RAINSHOWERS ARE POSSIBLE IN THE ATLANTIC OCEAN FROM 10N TO 18N BETWEEN AFRICA AND 21W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 36W TO THE SOUTH OF 24N...MOVING WESTWARD 10 TO 15 KNOTS. CONVECTIVE PRECIPITATION...ISOLATED MODERATE FROM 21N TO 23N BETWEEN 35W AND 37W. RAINSHOWERS ARE POSSIBLE WITHIN 120 NM TO 180 NM ON EITHER SIDE OF 24N34W 16N39W 10N42W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH SENEGAL NEAR 14N17W TO 12N21W...TO A 1011 MB LOW PRESSURE CENTER THAT IS NEAR 13N32W...TO 8N35W AND 7N40W. THE ITCZ CONTINUES FROM 7N40W TO 5N46W...AND INTO EXTREME NORTHEASTERN BRAZIL NEAR 3N52W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 4N TO 11N TO THE EAST OF 50W. ...DISCUSSION... FROM THE U.S.A. COASTAL WATERS OF THE ATLANTIC OCEAN...ACROSS CUBA...EVENTUALLY INTO THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N70W TO 28N71W...TO 23N79W BETWEEN ANDROS ISLAND IN THE BAHAMAS AND CUBA...TO 20N84W IN THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA...EVENTUALLY INTO THE GULF OF HONDURAS. THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 21/0000 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES... MIATPTPAN...IS 0.16 IN TEGUCIGALPA IN HONDURAS. CONVECTIVE PRECIPITATION...SCATTERED MODERATE IN THE ATLANTIC OCEAN FROM 26N TO 28N BETWEEN 70W AND 74W. ISOLATED MODERATE ELSEWHERE TO THE WEST AND NORTHWEST OF THE LINE THAT PASSES THROUGH 32N67W 26N69W 24N80W. CONVECTIVE PRECIPITATION IN THE CARIBBEAN SEA... ISOLATED MODERATE TO THE NORTH OF 16N TO THE WEST OF 80W. NUMEROUS STRONG IN EASTERN HONDURAS AND PARTS OF NORTH CENTRAL NICARAGUA...AND IN PARTS OF EASTERN EL SALVADOR. ISOLATED MODERATE TO THE SOUTH OF 20N TO THE EAST OF 94W IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...AND IN INTERIOR SECTIONS OF THE REST OF MEXICO TO THE EAST OF 93W. THE GULF OF MEXICO... A DEEP LAYER TROUGH IS MOVING EASTWARD THROUGH THE CENTRAL U.S.A. THE TROUGH SUPPORTS A COLD FRONT THAT IS MOVING THROUGH TEXAS...ALONG 30N97W...TO 27N100W AND 27N102W IN MEXICO...AND 28N106W. A STATIONARY FRONT CONTINUES FROM 28N106W BEYOND SOUTHWESTERN NEW MEXICO. CONVECTIVE PRECIPITATION...NUMEROUS STRONG EXTENDS FROM THE SOUTHERN HALF OF LOUISIANA...INTO THE ENTIRE COASTAL PLAINS SECTION OF TEXAS...INTO MEXICO NEAR 25N100W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE IN THE GULF OF MEXICO TO THE NORTH OF 24N TO THE WEST OF 93W. A 1004 MB LOW PRESSURE CENTER IS NEAR 24N97W ALONG THE MEXICO COAST. THE LOW CENTER IS MOVING NORTHWARD 10 TO 15 KNOTS. THE LOW CENTER HAS BEEN LOSING DEFINITION WITH TIME. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... MULTILAYERED CLOUD CEILINGS COVER THE WESTERN TWO-THIRDS OF THE ICAO STATIONS. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE ACROSS THE REST OF THE AREA. MULTILAYERED CLOUD CEILINGS AND STRONG PRECIPITATION COVER THE TEXAS COASTAL PLAINS...AND MOST OF THE LOUISIANA COASTAL PLAINS TO THE WEST OF 91W. OVERCAST HIGH CLOUDS ARE REPORTED AT THE NEW ORLEANS INTERNATIONAL AIRPORT. MULTILAYERED CLOUD CEILINGS AND PRECIPITATION COVER THE AREA FROM SOUTH CENTRAL MISSISSIPPI INTO SOUTHWESTERN COASTAL ALABAMA. MULTILAYERED CLOUD CEILINGS ARE FROM MARY ESTHER TO VALPARAISO. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT4...FOR MORE DETAILS ABOUT THE 1004 MB LOW PRESSURE CENTER THAT IS NEAR 24.5N97W. EXPECT 20 KNOT WINDS OR LESS AND SEA HEIGHTS TO 9 FEET WITHIN 390 NM OF THE CENTER IN THE NORTHEASTERN QUADRANT. HISPANIOLA... UPPER LEVEL SOUTHWESTERLY WIND FLOW SPANS THE AREA. THIS WIND FLOW IS RELATED TO THE ATLANTIC OCEAN-TO-NORTHWESTERN CARIBBEAN SEA MIDDLE LEVEL TO UPPER LEVEL TROUGH. THE CLOUD TOP TEMPERATURES HAVE BEEN WARMING WITH TIME IN THE NORTHERN HALF OF HAITI AND IN THE WESTERN SECTIONS OF THE DOMINICAN REPUBLIC...DURING THE LAST FEW HOURS. EARLIER CONVECTIVE PRECIPITATION HAS BEEN ENDING. THE GFS FORECAST FOR 700 MB AND FOR 500 MB SHOWS THAT ANTICYCLONIC WIND FLOW WILL COVER THE AREA. AN ANTICYCLONIC CIRCULATION CENTER WILL BE IN THE EAST CENTRAL-TO-CENTRAL CARIBBEAN SEA FOR THE ENTIRE TIME OF THE FORECAST PERIOD. THE GFS FORECAST FOR 250 MB SHOWS THAT A TROUGH WILL START ON A LINE THAT PASSES FROM THE BAHAMAS TO CENTRAL AND LATER EASTERN CUBA. THE TROUGH EVENTUALLY WILL PASS ON TOP OF HISPANIOLA. THE REST OF THE CARIBBEAN SEA... UPPER LEVEL WESTERLY AND SOUTHWESTERLY WIND FLOW COVER THE CARIBBEAN SEA TO THE WEST AND NORTHWEST OF THE LINE THAT RUNS FROM EASTERN HISPANIOLA TO 16N80W AND THE NORTHEASTERN CORNER OF NICARAGUA. THIS WIND FLOW IS RELATED TO THE ATLANTIC OCEAN-TO- NORTHWESTERN CARIBBEAN SEA MIDDLE LEVEL TO UPPER LEVEL TROUGH. NORTHERLY WIND FLOW COVERS THE CARIBBEAN SEA THAT IS TO THE SOUTH OF 15N TO THE WEST OF 74W. UPPER LEVEL SOUTHERLY WIND FLOW COVERS THE AREA THAT IS TO THE EAST OF 70W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 8N73W...ACROSS EASTERN PANAMA NEAR 8N78W...THROUGH WESTERN PANAMA...THROUGH NORTHERN COSTA RICA...BEYOND NORTHWESTERN NICARAGUA...INTO WESTERN HONDURAS. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IN EXTREME NORTHWESTERN VENEZUELA AND NORTHERN COLOMBIA FROM 8N TO 12N BETWEEN 72W AND 74W. NUMEROUS STRONG IN SOUTHWESTERN NICARAGUA...IN EASTERN HONDURAS AND PARTS OF NORTH CENTRAL NICARAGUA...AND IN PARTS OF EASTERN EL SALVADOR. THE REST OF THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 33N43W TO 31N44W. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N42W TO 29N50W 28N58W...TO A 1006 MB LOW PRESSURE CENTER THAT IS NEAR 27N62W. A SURFACE TROUGH CONTINUES FROM 27N62W TO 23N68W...ACROSS THE TURKS AND CAICOS...TO 21N74W TO THE WEST OF GREAT INAGUA ISLAND. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG FROM 29N TO 32N BETWEEN 40W AND 43W...FROM 26N TO 28N BETWEEN 57W AND 60W...AND FROM 23N TO 24N BETWEEN 61W AND 62W. ISOLATED TO WIDELY SCATTERED MODERATE IS ELSEWHERE WITHIN 150 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N55W 25N60W 22N67W 22N77W. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 22N51W. CYCLONIC WIND FLOW COVERS THE AREA FROM 17N TO 25N BETWEEN 47W AND 55W. A SURFACE TROUGH IS ALONG 17N54W...TO A 1011 MB LOW PRESSURE CENTER THAT IS NEAR 14N55W...TO 11N55W. CONVECTIVE PRECIPITATION...ISOLATED MODERATE FROM 13N TO 20N BETWEEN 50W AND 56W. A SURFACE RIDGE PASSES THROUGH 32N26W TO 27N33W. BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE AREA THAT IS TO THE NORTH OF 27N TO THE EAST OF 35W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR MORE DETAILS ABOUT THE 1006 MB LOW PRESSURE CENTER THAT IS NEAR 28N62W. EXPECT NORTHEAST TO EAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 FEET WITHIN 180 NM OF THE CENTER IN THE NORTHERN QUADRANT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT