000 AXNT20 KNHC 151200 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE DEC 15 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. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF NIGERIA NEAR 05N05E...TO 05N8W TO 04N11W. THE ITCZ CONTINUES FROM 04N11W TO 03N27W 01N37W 02N40W AND 02N43W. CONVECTIVE PRECIPITATION... ISOLATED MODERATE FROM 03N TO 07N BETWEEN 10W AND 13W...AND FROM 06N SOUTHWARD BETWEEN 21W AND 34W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE RAINSHOWERS ARE ELSEWHERE FROM 10N SOUTHWARD FROM 60W EASTWARD. ...DISCUSSION... ...THE GULF OF MEXICO... THE UPPER LEVEL ATMOSPHERIC SUPPORT FOR THE CURRENT GULF OF MEXICO COLD FRONT HAS BEEN RACING NORTHEASTWARD...NOW IN THE NEAR 47N76W IN CANADA. UPPER LEVEL SOUTHWESTERLY WIND FLOW AND COMPARATIVELY DRIER AIR IN SUBSIDENCE COVER MUCH OF THE AREA. A SLOWLY-MOVING COLD FRONT PASSES THROUGH FLORIDA NEAR 30N83W TO 27N86W AND 24N90W IN THE GULF OF MEXICO. THE FRONT IS STATIONARY AND DISSIPATING FROM 24N90W TO 21N95W AND 19N95W. A SURFACE TROUGH IS ALONG 24N88W 18N90W. CONVECTIVE PRECIPITATION... ISOLATED MODERATE FROM 26N TO 28N BETWEEN 83W AND 86W. RAINSHOWERS ARE POSSIBLE ALSO FROM 23N TO 30N BETWEEN 80W AND 89W. AN UPPER LEVEL RIDGE EXTENDS FROM EXTREME SOUTHERN GUATEMALA... THROUGH THE YUCATAN CHANNEL...BEYOND 32N70W IN THE ATLANTIC OCEAN. SURFACE HIGH PRESSURE AND ANTICYCLONIC WIND FLOW ARE TO THE NORTHWEST OF THE FRONTAL BOUNDARY. A 1011 MB HIGH PRESSURE CENTER IS NEAR 29N89W...OFF THE COAST OF SOUTHEASTERN LOUISIANA. FOR THE OFFSHORE OIL PLATFORM SITES AND/OR COASTAL SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... OBSERVATIONS SHOW THE MVFR CONDITIONS AT THE FOLLOWING ICAO STATIONS...KBBF AND KEMK. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... IFR CONDITIONS ARE BEING REPORTED IN TEXAS...AT MCALLEN. MVFR CONDITION ARE BEING REPORTED IN TEXAS ELSEWHERE IN THE RIO GRANDE VALLEY OF TEXAS...AND AT ALICE...AND IN PARTS OF THE LAKE CHARLES LOUISIANA METROPOLITAN AREA. IFR VISIBILITIES ARE BEING REPORTED IN THE NORTHERN PART OF THE HOUSTON METROPOLITAN AREA. LIFR CONDITIONS ARE BEING REPORTED AT SLIDELL IN LOUISIANA...IN PASCAGOULA MISSISSIPPI...AT THE NAVAL AIR STATION IN WHITING FIELD IN THE FLORIDA PANHANDLE...ALSO IN FLORIDA IN MARIANNA AND TALLAHASSEE. IFR CLOUD CONDITIONS ARE BEING REPORTED IN THE TAMPA-ST.PETERSBURG METROPOLITAN AREA...IN SARASOTA AND PUNTA GORDA...AND IN PARTS OF THE FORT MYERS METROPOLITAN AREA... IN SARASOTA AND IN NAPLES. LIFR CONDITIONS ARE FOUND IN PUNTA GORDA AND IN THE FORT MYERS METROPOLITAN AREA. ...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... ...HISPANIOLA... AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 19N77W... JUST OFF THE COAST OF SOUTHEASTERN CUBA. UPPER LEVEL CYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN AND THE CARIBBEAN SEA FROM THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO 28N BETWEEN PUERTO RICO AND 66W...AND THE YUCATAN PENINSULA OF MEXICO AND CENTRAL AMERICA. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 14N TO 17N BETWEEN 76W AND 79W. ISOLATED MODERATE ELSEWHERE FROM 12N TO 20N BETWEEN THE WINDWARD PASSAGE AND 79W. CONVECTIVE DEBRIS CLOUDS FROM EARLIER ALREADY- DISSIPATED PRECIPITATION AND OTHER POSSIBLE RAINSHOWERS ALSO ARE FROM 13N TO 23N BETWEEN 67W AND THE YUCATAN PENINSULA AND THE COAST OF CENTRAL AMERICA. CURRENT OBSERVATIONS...FOR PORT-AU-PRINCE IN HAITI...FEW LOW LEVEL CLOUDS AND SCATTERED HIGH LEVEL CLOUDS. NO NEW OBSERVATIONS ARE AVAILABLE FOR THE DOMINICAN REPUBLIC STATIONS AT THIS TIME. THE GFS MODEL AT 250 MB SHOWS THAT THE CURRENT UPPER LEVEL TROUGH WILL REMAIN FROM THE WINDWARD PASSAGE INTO THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA FOR THE FIRST 24 HOURS OF THE 48-HOUR FORECAST PERIOD. EXPECT SOUTHWESTERLY WIND FLOW FOR DAY ONE. THE TROUGH WILL MOVE EASTWARD WITH TIME DURING DAY TWO. CYCLONIC WIND FLOW WILL COVER HISPANIOLA DURING DAY TWO. THE GFS MODEL AT 500 MB PUTS A CYCLONIC CIRCULATION CENTER ABOUT 50 NM TO THE NORTH OF JAMAICA. THE CYCLONIC CENTER EVENTUALLY MOVES SOUTHEASTWARD DURING DAY ONE...ENDING UP ABOUT 75 NM TO THE SOUTHEAST OF JAMAICA. EXPECT SOUTHERLY WIND FLOW ACROSS HISPANIOLA DURING DAY ONE. THE ONE DOMINANT CYCLONIC CIRCULATION CENTER FROM DAY ONE EVOLVES INTO ONE COMPARATIVELY BROADER AREA OF CYCLONIC WIND FLOW WITH MULTIPLE CENTERS DURING DAY TWO. EXPECT BROAD CYCLONIC WIND FLOW ACROSS HISPANIOLA DURING DAY TWO. THE GFS MODEL AT 700 MB SHOWS THAT AN ANTICYCLONIC CIRCULATION CENTER WILL BE IN THE ATLANTIC OCEAN...ABOUT 420 NM TO THE NORTH OF HISPANIOLA AT THE START OF DAY ONE. THE ANTICYCLONIC WILL MOVE TO THE SOUTH AND BE ABOUT 330 NM TO THE NORTH OF HISPANIOLA BY THE END OF DAY ONE. THE ANTICYCLONIC CIRCULATION CENTER EVENTUALLY WILL MOVE NORTHWARD AGAIN...AND BE PRETTY MUCH NEAR THE SAME LOCATION AT THE END OF DAY TWO THAT IT HAD AT THE START OF THE 48-HOUR FORECAST PERIOD. THE 48-HOUR NET POSITION CHANGE WILL BE NEARLY STATIONARY. EXPECT SOUTHEASTERLY WIND FLOW ACROSS HISPANIOLA FOR THE NEXT 48 HOURS. EXPECT ALSO A FEW SHORT-LIVED INVERTED TROUGHS TO CROSS HISPANIOLA DURING THE NEXT 48 HOURS. ...THE REST OF THE CARIBBEAN SEA... UPPER LEVEL CYCLONIC WIND FLOW COVERS MUCH OF THE AREA. THIS WIND REGIME IS RELATED TO THE CYCLONIC WIND FLOW AND TROUGH THAT EXTEND FROM THE WINDWARD PASSAGE INTO THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. AN UPPER LEVEL RIDGE IS ALONG 62W. ...THE REST OF THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH PASSES THROUGH 32N37W TO 18N32W TO 09N33W. THE FIRST COLD FRONT PASSES THROUGH 32N21W TO 24N30W TO 19N45W. THE FRONT IS STATIONARY FROM 19N45W TO 20N58W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 28N TO 30N BETWEEN 57W AND 60W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG WITHIN 30 NM ON EITHER SIDE OF 32N23W 28N28W 23N31W. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 20N NORTHWARD BETWEEN 30W AND 60W. THE SECOND COLD FRONT PASSES THROUGH 32N34W TO 30N42W BEYOND 32N53W. SURFACE HIGH PRESSURE AND ANTICYCLONIC WIND FLOW COVER THE ATLANTIC OCEAN FROM 21N NORTHWARD BETWEEN 53W AND 80W. A 1020 MB HIGH PRESSURE CENTER IS NEAR 28N61W. A SURFACE RIDGE KS ALONG 20N26W BEYOND 24N16W INTO AFRICA. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ MT