000 AXNT20 KNHC 180605 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST THU DEC 17 2015 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 FEATURES... ...FOR THE GULF OF MEXICO...THE FORECAST FOR THE NEXT 12 HOURS INDICATES THAT A COLD FRONT WILL BE ALONG 30N80W 20N93W. EXPECT GALE-FORCE NORTHWEST TO NORTH WINDS AND SEA HEIGHTS RANGING FROM 8 FEET TO 11 FEET TO THE SOUTH OF 24N TO THE WEST OF THE FRONT TO 96W. PLEASE READ THE HIGH SEAS FORECAST... MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST... MIAOFFNT4/FZNT24 KNHC...FOR MORE DETAILS ABOUT... ...FOR THE ATLANTIC OCEAN...PLEASE REFER TO THE METEO-FRANCE HIGH SEAS FORECAST THAT IS LISTED UNDER MARINE...BULLETINS EXPERTISES...GRAND LARGE...METAREA II...ON THE WEBSITES WWW.METEO.FR...OR WWW.METEOFRANCE.COM...FOR GALE-FORCE WINDS THAT ARE FORECAST FOR THE AREA THAT IS CALLED IRVING. GALE-FORCE WINDS ARE FORECAST TO DEVELOP IN ABOUT 12 HOURS...IN THE GULF OF TEHUANTEPEC ON THE EASTERN PACIFIC OCEAN SIDE OF SOUTHERN MEXICO. STORM-FORCE WINDS ARE FORECAST TO DEVELOP IN ABOUT 24 HOURS IN THE GULF OF TEHUANTEPEC. PLEASE READ THE EASTERN PACIFIC OCEAN HIGH SEAS FORECAST...MIAHSFEP2/FZPN03 KNHC...AND THE EASTERN PACIFIC OCEAN TROPICAL WEATHER DISCUSSION...MIATWDEP/AXPZ20 KNHC...FOR MORE DETAILS. ...THE ITCZ/THE MONSOON TROUGH... THE ITCZ IS ALONG 05N20W 05N25W 04N32W 03N37W...TO THE EQUATOR ALONG 48W. A SURFACE TROUGH IS ALONG 32W/33W FROM 09N SOUTHWARD. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 04N TO 07N BETWEEN 29W AND 37W. ISOLATED MODERATE ELSEWHERE FROM 10N SOUTHWARD FROM 60W EASTWARD. ...DISCUSSION... ...THE GULF OF MEXICO... A DEEP LAYER TROUGH PASSES THROUGH THE CENTRAL U.S.A...THROUGH MISSOURI INTO THE EASTERN HALF OF TEXAS. UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE GULF OF MEXICO. THE TROUGH IS SUPPORTING A COLD FRONT THAT PASSES THROUGH THE FLORIDA BIG BEND NEAR 30N84W...TO THE CENTRAL GULF OF MEXICO NEAR 24N90W...INTO THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...AT THE NORTHERN PART OF THE ISTHMUS OF TEHUANTEPEC. A SURFACE RIDGE PASSES THROUGH THE DEEP SOUTH OF TEXAS...ALONG THE MEXICO COAST... TO THE ISTHMUS OF TEHUANTEPEC OF SOUTHERN MEXICO. CONVECTIVE PRECIPITATION...ISOLATED MODERATE WITHIN 30 NM TO 60 NM ON EITHER SIDE OF 27N84W 22N88W. RAINSHOWERS ARE POSSIBLE ELSEWHERE IN THE GULF OF MEXICO TO THE WEST AND NORTHWEST OF THE 27N84W 22N88W LINE. ...FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... VFR CONDITIONS ARE BEING REPORTED. ...LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... LIFR CONDITIONS ARE BEING REPORTED IN FLORIDA AT...APALACHICOLA IFR CONDITIONS AT...TALLAHASSEE...AT ST. PETERSBURG AND CLEARWATER. MVFR CONDITIONS IN FLORIDA AT...PERRY AND BROOKSVILLE. ...FROM THE WESTERN SECTIONS OF THE ATLANTIC OCEAN...ACROSS THE BAHAMAS AND CUBA...INTO THE WESTERN SECTIONS OF THE CARIBBEAN SEA...INCLUDING CROSSING HISPANIOLA...AND THE REST OF THE CARIBBEAN SEA... AN UPPER LEVEL TROUGH EXTENDS FROM A 22N69W ATLANTIC OCEAN CYCLONIC CIRCULATION CENTER...ACROSS HISPANIOLA...TO 14N74W IN THE CARIBBEAN SEA...TO EASTERN PANAMA IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. LARGE-SCALE UPPER LEVEL CYCLONIC WIND FLOW COVERS THE CARIBBEAN SEA TO THE SOUTHEAST OF THE LINE THAT RUNS FROM 21N79W AT THE COAST OF CUBA TO EASTERN COASTAL HONDURAS. CONVECTIVE PRECIPITATION...BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE RAINSHOWERS ARE FROM 12N TO 22N BETWEEN 60W AND 80W. RAINSHOWERS ARE POSSIBLE ALSO IN PATCHES OF CLOUDS THAT ARE MOVING NORTHWESTWARD...FROM 12N NORTHWARD FROM 80W WESTWARD. RAINSHOWERS ARE POSSIBLE FROM 10N TO 12N BETWEEN 56W AND 63W... MOVING WESTWARD FROM THE ATLANTIC OCEAN THROUGH THE SOUTHEASTERN CORNER OF THE CARIBBEAN SEA. AN UPPER LEVEL RIDGE EXTENDS FROM GUATEMALA TO THE YUCATAN PENINSULA AND THE YUCATAN CHANNEL...TO THE STRAITS OF FLORIDA. AN UPPER LEVEL RIDGE ALSO IS ALONG 61W IN THE EASTERN PART OF THE CARIBBEAN SEA. CURRENT OBSERVATIONS...FOR THE DOMINICAN REPUBLIC...RAINSHOWERS WITH THUNDER ARE BEING REPORTED IN SANTO DOMINGO. FEW LOW LEVEL CLOUDS AND SCATTERED MIDDLE LEVEL CLOUDS ARE IN LA ROMANA. A LOW LEVEL CLOUD CEILING IS IN PUNTA CANA. FEW CUMULONIMBUS CLOUDS ARE IN SANTIAGO. FEW LOW LEVEL CLOUDS ARE IN PUERTO PLATA. THE GFS MODEL AT 250 MB SHOWS THAT THE CURRENT UPPER LEVEL CYCLONIC CIRCULATION CENTER AND TROUGH WILL CONTINUE TO AFFECT THE AREA FOR THE NEXT 48 HOURS OR SO. THE CYCLONIC CENTER WILL MOVE ON TOP OF HISPANIOLA AT THE END OF DAY ONE. THE CYCLONIC CENTER WILL BECOME ELONGATED AND WEAKEN AS AN ORGANIZED CENTER DURING DAY TWO. EXPECT NORTHWESTERLY WIND FLOW BY THE END OF DAY TWO. THE GFS MODEL AT 500 MB SHOWS THAT EAST-TO-SOUTHEAST WIND FLOW WILL BE MOVING ACROSS HISPANIOLA FOR THE NEXT 48 HOURS. AN INVERTED TROUGH WILL REMAIN ACROSS THE AREA. THE GFS MODEL AT 700 MB SHOWS THAT EAST TO SOUTHEAST WIND FLOW WILL MOVE ACROSS HISPANIOLA DURING THE NEXT 48 HOURS. EXPECT ALSO A FEW SHORT- LIVED INVERTED TROUGHS TO CROSS HISPANIOLA DURING THE NEXT 48 HOURS. ...THE REST OF THE ATLANTIC OCEAN... AN ATLANTIC OCEAN UPPER LEVEL TROUGH PASSES THROUGH 32N38W TO 26N42W AND 21N45W. A COLD FRONT PASSES THROUGH 32N32W TO 27N40W 25N50W 25N57W. THE COLD FRONT IS DISSIPATING FROM 25N57W TO 25N64W. A PRE-FRONTAL TROUGH IS ALONG 30N29W 24N36W. CONVECTIVE PRECIPITATION...ISOLATED MODERATE WITHIN 30 NM ON EITHER SIDE OF THE LINE THROUGH 32N30W TO 29N35W. RAINSHOWERS ARE POSSIBLE...TO THE NORTH AND NORTHWEST OF THE LINE THAT PASSES THROUGH 32N24W 20N38W 14N49W 14N60W 30N80W. SURFACE ANTICYCLONIC WIND FLOW IS TO THE NORTH AND NORTHWEST OF THE 32N32W 25N64W COLD FRONT BETWEEN 45W AND 70W. A SURFACE RIDGE ALSO EXTENDS FROM A 1027 MB HIGH PRESSURE CENTER THAT IS NEAR 33N56W TO 29N70W...ACROSS THE NORTHWESTERN BAHAMAS OF GRAND BAHAMA ISLAND AND GREAT ABACO...TO 24N85W IN THE SOUTHEASTERN GULF OF MEXICO. A SURFACE RIDGE EXTENDS FROM A 1031 MB MOROCCO HIGH PRESSURE CENTER THAT IS NEAR 31N05W TO 28N09W 26N16W 26N25W...TO 20N50W...AND TO 28N74W. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ MT