000 AXNT20 KNHC 111125 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI OCT 11 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... A 1008 MB LOW PRESSURE CENTER IS NEAR 11N35W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 10N TO 12N BETWEEN 34W AND 41W. SCATTERED STRONG ELSEWHERE FROM 10N TO 14N BETWEEN 33W AND 44W. UPPER LEVEL WINDS ARE BECOMING LESS CONDUCIVE FOR TROPICAL CYCLONE FORMATION. SOME DEVELOPMENT OF THIS SYSTEM STILL IS POSSIBLE DURING THE NEXT DAY OR SO...BEFORE UPPER LEVEL WINDS BECOME EVEN LESS CONDUCIVE DURING THIS WEEKEND. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. THE SYSTEM IS FORECAST TO MOVE WESTWARD TO WEST- NORTHWESTWARD ABOUT 10 KNOTS. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 54W/55W TO THE SOUTH OF 20N MOVING WESTWARD 10 TO 15 KNOTS. CONVECTIVE PRECIPITATION... WIDELY SCATTERED TO SCATTERED MODERATE TO ISOLATED STRONG FROM 16N TO 23N BETWEEN 49W AND 57W. A CARIBBEAN SEA TROPICAL WAVE IS ALONG 79W/80W TO THE SOUTH OF 18N MOVING WESTWARD 10 KNOTS. A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE WESTERN ATLANTIC OCEAN NEAR 32N67W... ACROSS HISPANIOLA...INTO THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. THE TROUGH HAS BEEN WEAKENING IN ITS SATELLITE IMAGERY REPRESENTATION AS COMPARED TO THE IMAGERY OF 24 HOURS AGO. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG IN THE ATLANTIC OCEAN TO THE NORTH OF 20N BETWEEN 60W AND 75W. ISOLATED MODERATE IN THE CARIBBEAN SEA FROM 17N TO 20N BETWEEN 65W AND THE WINDWARD PASSAGE. ISOLATED MODERATE CONVECTIVE PRECIPITATION COVERS THE REST OF THE CARIBBEAN SEA TO THE SOUTH OF 17N TO THE EAST OF 70W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA NEAR 11N15W... TO 5N20W 7N28W...TO THE 1008 MB LOW PRESSURE CENTER THAT IS NEAR 11N35W...TO 9N40W AND 8N45W. THE ITCZ CONTINUES FROM 8N45W TO 9N50W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 10N TO 12N BETWEEN 14W AND 16W...AND WITHIN A 30 NM RADIUS OF 10N18W. SCATTERED MODERATE TO ISOLATED STRONG FROM 1N TO 11N BETWEEN 20W AND 30W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 6N TO 10N BETWEEN 30W AND 40W. ...DISCUSSION... FROM THE U.S.A. EAST COAST...ACROSS FLORIDA...INTO THE FLORIDA STRAITS...WESTERN CUBA...ACROSS THE YUCATAN PENINSULA...INTO THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...AND THE REST OF THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH FLORIDA AND THE ADJACENT ATLANTIC OCEAN COASTAL WATERS OF FLORIDA...ACROSS WESTERN CUBA...INTO THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA...EVENTUALLY TO 13N81W IN THE WESTERN CARIBBEAN SEA. COMPARATIVELY DRIER AIR IN SUBSIDENCE...AS SEEN IN WATER VAPOR IMAGERY...COVERS THE GULF OF MEXICO...EXCEPT FOR THE WEAK PRECIPITATION THAT IS IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...TO THE SOUTH OF 24N TO THE WEST OF 90W. A SURFACE RIDGE PASSES THROUGH THE WESTERN FLORIDA PANHANDLE TO 28N87W THROUGH THE YUCATAN CHANNEL...INTO THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N70W TO 29N71W AND 26N74W. THE REST OF THE BOUNDARY IS DISSIPATING ALONG 26N74W...ALONG THE SOUTHERN BORDER OF ANDROS ISLAND IN THE BAHAMAS...TO WESTERN CUBA NEAR 22N81W. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG WITHIN 60 NM TO 120 NM ON EITHER SIDE OF 27N75W 19N78W 13N83W. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... LOW CLOUD CEILINGS ARE BEING REPORTED AT THE FOLLOWING ICAO STATIONS...KVAF...KHQI...KGUL...KEHK...AND KGBK. FAIR SKIES/ CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE ACROSS THE AREA. SCATTERED TO BROKEN LOW CLOUDS COVER THE COASTAL PLAINS OF TEXAS FROM THE MIDDLE TEXAS COAST SOUTHWARD. VISIBILITIES OF 3 MILES OR LESS AND FOG COVER COASTAL SECTIONS OF LOUISIANA...INCLUDING ALONG THE NORTHERN SIDE OF LAKE PONTCHARTRAIN...IN SOUTHEASTERN MISSISSIPPI...AND COASTAL ALABAMA...IN FLORIDA IN CRESTVIEW AND AT THE NAVAL AIR STATION WHITING FIELD...AND IN BROOKSVILLE. FROM THE WESTERN ATLANTIC OCEAN INTO THE CARIBBEAN SEA... INCLUDING ACROSS HISPANIOLA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE WESTERN ATLANTIC OCEAN NEAR 32N67W...ACROSS HISPANIOLA...INTO THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. THE TROUGH HAS BEEN WEAKENING IN ITS SATELLITE IMAGERY REPRESENTATION AS COMPARED TO THE IMAGERY OF 24 HOURS AGO. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG IN THE COASTAL WATERS OF HISPANIOLA AND PUERTO RICO. SCATTERED MODERATE TO ISOLATED STRONG IN THE ATLANTIC OCEAN FROM 20N NORTHWARD BETWEEN 59W AND 76W. WIDELY SCATTERED MODERATE IN THE CARIBBEAN SEA ELSEWHERE BETWEEN 60W AND 73W. ISOLATED MODERATE IN THE CARIBBEAN SEA FROM 17N TO 20N BETWEEN 65W AND THE WINDWARD PASSAGE. THE GFS FORECAST FOR 700 MB SHOWS THAT AN INVERTED TROUGH WILL SPAN THE ISLAND FOR THE FIRST 12 HOURS OF THE FORECAST PERIOD...AND FOR THE LAST 18 HOURS OF THE FORECAST PERIOD. ANTICYCLONIC WIND FLOW WITH A RIDGE WILL COVER HISPANIOLA FOR THE REST OF THE TIME. THE GFS FORECAST FOR 500 MB STARTS WITH HISPANIOLA BEING IN THE MIDDLE OF A RIDGE THAT IS TO THE NORTH OF THE AREA AND AN INVERTED TROUGH THAT IS TO THE SOUTH OF THE AREA. ANTICYCLONIC WIND FLOW WITH A RIDGE EVENTUALLY RETURNS AND LASTS FOR THE REST OF THE 48 HOUR FORECAST PERIOD. THE GFS FORECAST FOR 250 MB SHOWS THAT A NORTHEAST-TO-SOUTHWEST ORIENTED TROUGH WILL CUT ACROSS THE AREA FOR THE FIRST 24 HOURS OF THE FORECAST PERIOD. HISPANIOLA WILL BE ON THE EASTERN SIDE OF A DIFFERENT TROUGH FOR THE NEXT 24 HOURS AFTER THAT. THE TROUGH IS FORECAST TO MOVE FROM 80W EASTWARD. THE REST OF THE CARIBBEAN SEA... THE MONSOON TROUGH IS ALONG 9N74W IN COLOMBIA...TO 9N80W IN PANAMA...BEYOND 9N84W IN SOUTHERN COSTA RICA...INTO THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 6N IN COLOMBIA TO 11N IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA BETWEEN 73W AND 79W...AND ALONG THE EASTERN SHORES OF LAKE MARACAIBO IN NORTHWESTERN VENEZUELA. 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 TO 8 FEET FROM 12N TO 14N BETWEEN 68W AND 74W. THE REST OF THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N32W TO 27N34W TO 23N41W...TO A CUT-OFF CYCLONIC CIRCULATION CENTER THAT IS NEAR 19N47W...TO A SECOND CUT-OFF CYCLONIC CIRCULATION CENTER THAT IS NEAR 19N55W. THE 19N55W CYCLONIC CENTER IS NEAR THE 54W/55W TROPICAL WAVE. THE TROUGH WAS SUPPORTING A FRONTAL BOUNDARY SIX HOURS AGO. THE FRONTAL BOUNDARY HAS WEAKENED AND DISSIPATED. A REMNANT CLOUD LINE...WITH ISOLATED MODERATE CONVECTIVE PRECIPITATION...IS WITHIN 30 NM TO 60 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N23W 27N27W 25N33W 25N43W. OTHER CLOUDS AND POSSIBLE PRECIPITATION ARE TO THE NORTH OF 25N BETWEEN 40W AND 50W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR MORE DETAILS ABOUT A 1008 MB LOW PRESSURE CENTER...A POSSIBLE TROPICAL CYCLONE...NEAR 11N35W. EXPECT NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS FROM 8 TO 11 FEET FROM 11N TO 18N TO THE EAST OF 41W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT