000 AXNT20 KNHC 191142 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE NOV 19 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 1115 UTC. ...SPECIAL FEATURE... THE CENTER OF SUBTROPICAL STORM MELISSA AT 19/0900 UTC IS NEAR 31.2N 54.6W...ABOUT 970 KM/524 NM...TO THE EAST OF BERMUDA. MELISSA IS MOVING NORTHWARD 8 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 982 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 55 KNOTS WITH GUSTS TO 65 KNOTS. PUBLIC ADVISORIES ON SUBTROPICAL STORM MELISSA ARE ISSUED UNDER WMO HEADER WTNT34 KNHC AND UNDER AWIPS HEADER MIATCPAT4. FORECAST/ADVISORIES ON SUBTROPICAL STORM MELISSA ARE ISSUED UNDER WMO HEADER WTNT24 KNHC AND UNDER AWIPS HEADER MIATCMAT4. LARGE SWELLS WILL CONTINUE TO AFFECT BERMUDA...SECTIONS OF THE NORTHERN LEEWARD ISLANDS...PUERTO RICO...HISPANIOLA...AND THE SOUTHEASTERN BAHAMAS DURING THE NEXT COUPLE OF DAYS...CAUSING LIFE- THREATENING SURF AND RIP CURRENTS. PLEASE REFER TO STATEMENTS FROM YOUR LOCAL WEATHER SERVICE OFFICE FOR MORE DETAILS. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 31N TO 34N BETWEEN 52W AND 56W. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 23N TO 32N BETWEEN 50W AND 60W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...FOR MORE DETAILS ABOUT THE WINDS AND SEA HEIGHTS THAT ACCOMPANY SUBTROPICAL STORM MELISSA. A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS IN THE ATLANTIC OCEAN FROM A 31N55W CYCLONIC CIRCULATION CENTER...TO 19N56W 14N57W... BEYOND 10N60W INTO VENEZUELA. CYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN BETWEEN 47W AND 80W. UPPER LEVEL SOUTHWESTERLY WIND FLOW IS STREAMING FROM SOUTHERN VENEZUELA...ACROSS NORTHEASTERN VENEZUELA AND GUYANA BEYOND 14N56W IN THE ATLANTIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 12N TO 32N BETWEEN 43W AND 54W...WITHIN 300 NM ON EITHER SIDE OF 12N50W 24N47W BEYOND 32N46W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES ACROSS COASTAL GUINEA NEAR 8N13W TO 5N18W. THE ITCZ CONTINUES FROM 5N18W TO 4N28W 8N37W AND 8N42W. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 2N TO 4N BETWEEN 18W AND 23W...FROM 7N TO 9N BETWEEN 33W AND 36W...AND FROM 7N TO 10N BETWEEN 41W AND 45W. SCATTERED MODERATE TO ISOLATED STRONG FROM 4N TO 7N BETWEEN 22W AND 30W...AND FROM 8N TO 10N BETWEEN 47W AND 51W. ...DISCUSSION... THE GULF OF MEXICO... MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE GULF OF MEXICO. A RIDGE PASSES THROUGH THE FLORIDA PANHANDLE BEYOND THE YUCATAN PENINSULA. THE BASE OF A MIDDLE LEVEL TO UPPER LEVEL TROUGH REACHES 32N72W IN THE ATLANTIC OCEAN. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N76W IN THE ATLANTIC OCEAN...TO 30N82W IN NORTHERN FLORIDA...TO 28N90W...TO THE TEXAS GULF COAST NEAR 27N98W...TO NORTHERN MEXICO 29N102W. A SURFACE TROUGH IS WITHIN 60 TO 120 NM TO THE SOUTH OF THE FRONT FROM 27N TO 32N BETWEEN 75W AND 84W. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 23N TO 27N BETWEEN 92W AND 96W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND OTHER POSSIBLE PRECIPITATION ARE TO THE NORTH OF 22N98W 23N90W 26N82W. SURFACE ANTICYCLONIC WIND FLOW IS TO THE SOUTH OF THE FRONT AND TROUGH. A 1016 MB HIGH PRESSURE CENTER IS NEAR 25N92W. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... LOW CLOUD CEILINGS ARE OBSERVED AT THE FOLLOWING ICAO STATIONS...KMZG...KBBF...KBQX...KVAF...KEMK...KGUL...KHQI... KEHC.....KEIR...KSPR...AND K9FW. MIDDLE LEVEL CEILINGS ARE BEING OBSERVED AT THE FOLLOWING ICAO STATIONS KEHC...KGBK...KIPN... KMDJ...KDLP...AND KAXO. LOW CLOUD CEILINGS COVER TEXAS FROM GALVESTON SOUTHWARD TO THE DEEP SOUTH OF TEXAS. MIDDLE AND HIGH LEVEL CLOUD CEILINGS ARE IN THE HOUSTON METROPOLITAN AREA. MIDDLE LEVEL CLOUD CEILINGS COVER COASTAL LOUISIANA. MIDDLE LEVEL AND HIGH LEVEL CLOUD CEILINGS ARE BEING OBSERVED AND/OR HAVE BEEN OBSERVED ALONG THE SOUTHERN SIDE OF LAKE PONTCHARTRAIN IN LOUISIANA DURING THE LAST FEW HOURS. A HIGH CLOUD CEILING IS IN VALPARAISO IN THE FLORIDA PANHANDLE. LOW CLOUD CEILINGS COVER THE FLORIDA COAST FROM BROOKSVILLE TO THE TAMPA METROPOLITAN AREA...TO SARASOTA...AND IN MARATHON KEY. MIDDLE LEVEL CLOUD CEILINGS ARE IN PUNTA GORDA AND NAPLES. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT4/FZNT24 KNHC...FOR MORE DETAILS ABOUT THE COLD FRONT FROM 29N83W TO 28N98W. EXPECT NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS LOWER THAN 8 FEET TO THE NORTH OF THE FRONT TO THE WEST OF 85W. ...HISPANIOLA... LARGE SWELLS FROM SUBTROPICAL STORM MELISSA WILL CONTINUE TO AFFECT HISPANIOLA...PUERTO RICO...SECTIONS OF THE NORTHERN LEEWARD ISLANDS...AND THE SOUTHEASTERN BAHAMAS DURING THE NEXT COUPLE OF DAYS...CAUSING LIFE-THREATENING SURF AND RIP CURRENTS. PLEASE REFER TO STATEMENTS FROM YOUR LOCAL WEATHER SERVICE OFFICE FOR MORE DETAILS. MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW IS MOVING ACROSS HISPANIOLA. THIS WIND FLOW IS RELATED TO THE CYCLONIC WIND FLOW THAT IS MOVING AROUND THE TROUGH THAT IS PART OF SUBTROPICAL STORM MELISSA. COMPARATIVELY DRIER AIR...APPARENT IN WATER VAPOR SATELLITE IMAGERY...ALSO COVERS HISPANIOLA. SCATTERED TO BROKEN LOW LEVEL AND MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS COVER HISPANIOLA. CONVECTIVE PRECIPITATION...BROKEN LOW LEVEL TO MIDDLE LEVEL CLOUDS AND ISOLATED MODERATE TO LOCALLY STRONG FROM 12N TO 18N BETWEEN 71W AND 80W. THE GFS FORECAST FOR 250 MB SHOWS THAT NORTHWESTERLY WIND FLOW WILL PASS ON TOP OF HISPANIOLA DURING THE NEXT 48 HOURS. AN ATLANTIC OCEAN TROUGH WILL SHIFT SLIGHTLY WESTWARD WITH TIME. THE GFS FORECAST FOR 500 MB SHOWS THAT NORTHWESTERLY TO NORTHERLY WIND FLOW WILL PASS ON TOP OF HISPANIOLA FOR THE FIRST 24 HOURS OF THE 48 HOUR FORECAST PERIOD. HISPANIOLA WILL BE IN NEARLY A COL FOR THE SECOND HALF OF THE FORECAST PERIOD AFTER THE SOUTHERN PART OF THE TROUGH WEAKENS AND DISSIPATES. THE NORTHERN PART OF THE TROUGH REMAINS INTACT...FROM 19N59W BEYOND 23N56W IN THE ATLANTIC OCEAN. THE GFS FORECAST FOR 700 MB STARTS WITH NORTHERLY WIND FLOW ACROSS THE AREA FOR ABOUT 6 HOURS OR SO. HISPANIOLA ALSO ENDS UP NEARLY IN A COL FOR MOST OF THE REST OF THE 48 HOUR FORECAST PERIOD. SOUTHEASTERLY WIND FLOW ENDS UP MOVING ACROSS THE AREA FOR THE LAST 12 HOURS OR SO. THE REST OF THE CARIBBEAN SEA... CONVECTIVE PRECIPITATION...BROKEN LOW LEVEL TO MIDDLE LEVEL CLOUDS AND ISOLATED MODERATE TO LOCALLY STRONG FROM 12N TO 18N BETWEEN 71W AND 80W...AND FROM 13N TO 19N BETWEEN 80W AND 88W. BROKEN LOW LEVEL TO MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS COVER THE AREA THAT IS TO THE SOUTH OF 20N TO THE EAST OF 70W. MIDDLE LEVEL TO UPPER LEVEL CYCLONIC WIND FLOW COVERS THE AREA THAT IS TO THE EAST OF 75W. THE CYCLONIC WIND FLOW IS ASSOCIATED WITH THE WIND FLOW THAT IS MOVING AROUND SUBTROPICAL STORM MELISSA IN THE ATLANTIC OCEAN. MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE CARIBBEAN SEA THAT IS TO THE WEST OF 75W. THE MONSOON TROUGH IS ALONG 10N74W IN COLOMBIA...THROUGH 8N81W IN PANAMA...BEYOND 8N83W IN SOUTHERN COSTA RICA...INTO THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...RAINSHOWERS ARE POSSIBLE TO THE SOUTH OF 12N TO THE WEST OF 76W. NUMEROUS STRONG IS ALONG THE EASTERN PACIFIC OCEAN COAST OF COLOMBIA AND TO THE SOUTH OF PANAMA FROM 5N TO 7N TO THE EAST OF 80W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE FROM 4N TO 10N TO THE EAST OF 80W IN THE EASTERN PACIFIC OCEAN. THE REST OF THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE SOUTHERN HALF OF THE WESTERN SAHARA...TO A 21N23W DEVELOPING CYCLONIC CIRCULATION CENTER...TO 10N24W. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY. A SURFACE RIDGE PASSES THROUGH 32N29W TO 23N34W 17N37W...TO 10N46W. THIS RIDGE IS TO THE EAST OF SUBTROPICAL STORM MELISSA. SURFACE ANTICYCLONIC WIND FLOW COVERS THE AREA THAT IS FROM 20N TO 32N BETWEEN 65W AND 80W. THIS PART OF THE ATLANTIC OCEAN IS BETWEEN SUBTROPICAL STORM MELISSA TO THE EAST AND AN APPROACHING COLD FRONT THAT IS TO THE NORTHWEST. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...FOR MORE DETAILS ABOUT THE WINDS AND SEA HEIGHTS THAT ACCOMPANY SUBTROPICAL STORM MELISSA. A SECOND AREA OF INTEREST CONSISTS OF THE 6 HOUR FORECAST OF A COLD FRONT FROM 31N72W TO 27N81W. EXPECT NORTH TO NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 FEET TO THE NORTH OF 30N TO THE WEST OF THE FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT