000 AXNT20 KNHC 150558 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF SIERRA LEONE NEAR 08N13W TO 05N16W. THE ITCZ CONTINUES FROM 05N16W TO 03N22W 04N28W 03N36W 04N42W...INTO NORTHEASTERN BRAZIL NEAR 01N52W. CONVECTIVE PRECIPITATION...ISOLATED MODERATE FROM 07N SOUTHWARD FROM 36W EASTWARD. 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 IS RACING NORTHEASTWARD...NOW IN THE AREA OF THE U.S.A. GREAT LAKES. UPPER LEVEL SOUTHWESTERLY WIND FLOW AND COMPARATIVELY DRIER AIR IN SUBSIDENCE COVER MUCH OF THE AREA. A 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 TO WIDELY SCATTERED MODERATE FROM 25N TO 30N BETWEEN 83W AND 86W. RAINSHOWERS ARE POSSIBLE ALSO FROM 19N TO 24N BETWEEN 88W AND 91W. AN UPPER LEVEL RIDGE EXTENDS FROM EXTREME SOUTHEASTERN MEXICO... NEAR ITS BORDER WITH GUATEMALA...ACROSS THE NORTHERN PART OF THE YUCATAN PENINSULA...BEYOND 32N74W 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 29N92W...OFF THE COAST OF 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 MVFR CLOUD CONDITIONS AT THE FOLLOWING ICAO STATIONS...KVOA. IFR VISIBILITIES ARE BEING REPORTED AT THE FOLLOWING ICAO STATIONS...VICTORIA TEXAS. LIFR CONDITIONS ARE BEING REPORTED AT THE FOLLOWING ICAO STATIONS...HOUSTON- PEARLAND REGIONAL AIRPORT...AND IN THE LAKE CHARLES LOUISIANA METROPOLITAN AREA. LIFR CONDITIONS ARE BEING REPORTED IN FLORIDA IN MARIANNA. IFR VISIBILITIES ARE BEING REPORTED IN FLORIDA IN PANAMA CITY. MVFR CONDITIONS ARE BEING REPORTED IN APALACHICOLA AND PERRY. LIFR CLOUDS ARE BEING REPORTED IN FLORIDA IN THE AREA OF BROOKSVILLE-TAMPA...ELSEWHERE IN THE TAMPA-ST.PETERSBURG METROPOLITAN AREA...IN SARASOTA AND PUNTA GORDA...AND IN PARTS OF 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... A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG 26N72W...ACROSS THE BAHAMAS AND SOUTHEASTERN CUBA...TO A 17N79W CYCLONIC CIRCULATION CENTER THAT IS TO THE SOUTH OF JAMAICA...INTO THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA AND WESTERN SECTIONS OF COASTAL PANAMA. AN ATLANTIC OCEAN SURFACE TROUGH IS ALONG 28N69W 21N72W...ACROSS HAITI JUST TO THE WEST OF ITS BORDER WITH THE DOMINICAN REPUBLIC...TO NORTHERN COLOMBIA NEAR 11N73W. A SECOND SURFACE TROUGH IS ALONG 19N78W 17N80W 14N80W. CONVECTIVE PRECIPITATION...SCATTERED STRONG WITHIN A 15 NM TO 30 NM RADIUS OF 14N74.5W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 16N TO 20N BETWEEN PUERTO RICO AND 80W IN THE CARIBBEAN SEA...AND FROM 20N TO 24N BETWEEN 69W AND 76W...INCLUDING IN HISPANIOLA AND SOUTHEASTERN CUBA AND ACROSS THE BAHAMAS. IN THE ATLANTIC OCEAN...WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 24N TO 28N BETWEEN 67W AND 72W. RAINSHOWERS ARE POSSIBLE ELSEWHERE IN THE ATLANTIC OCEAN FROM 20N TO 30N BETWEEN 50W AND THE FLORIDA EAST COAST. ...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/63W. ...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 BELIZE. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 14N TO 16N BETWEEN 78W AND 79W. ISOLATED MODERATE ELSEWHERE WITHIN 60 NM ON EITHER SIDE OF 19N76W 17N78W 13N80W. CONVECTIVE DEBRIS CLOUDS FROM EARLIER ALREADY-DISSIPATED PRECIPITATION AND POSSIBLE RAINSHOWERS ALSO ARE FROM 13N TO 23N BETWEEN 67W AND THE YUCATAN PENINSULA AND THE COAST OF CENTRAL AMERICA. CURRENT OBSERVATIONS...THE LAST OBSERVATION FOR PORT-AU-PRINCE IN HAITI FOR 15/0100 UTC SHOWED FEW LOW LEVEL CLOUDS. IN THE DOMINICAN REPUBLIC...FEW CUMULONIMBUS CLOUDS AND OTHER SCATTERED LOW LEVEL CLOUDS ARE IN SANTO DOMINGO. FEW LOW LEVEL CLOUDS ARE IN LA ROMANA. RAINSHOWERS ARE BEING OBSERVED IN PUNTA CANA. SCATTERED LOW LEVEL CLOUDS ARE IN SANTIAGO. FEW LOW LEVEL CLOUDS ARE IN PUERTO PLATA. 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 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 21N57W. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG WITHIN 30 NM ON EITHER SIDE OF 31N22W 29N24W 27N28W 26N29W 25N31W 24N31W 22N34W. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 20N NORTHWARD BETWEEN 30W AND 60W. THE SECOND COLD FRONT PASSES THROUGH 32N39W TO 31N46W BEYOND 32N54W. A PRE-FRONTAL TROUGH IS ALONG 32N37W 29N42W 28N49W. 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 30N65W. A SURFACE RIDGE PASSES THROUGH MOROCCO NEAR 28N10W TO 26N16W... TO A 1015 MB HIGH PRESSURE CENTER THAT IS NEAR 16N36W...TO 15N59W. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ MT