000 AGXX40 KNHC 041819 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 119 PM EST MON JAN 4 2016 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: BLEND OF GFS/WW3/NWPS GUIDANCE WITH PREVIOUS OFFICIAL FORECAST. MEDIUM CONFIDENCE. OBSERVATIONS SHOWED SEAS WERE INITIALLY RUNNING 1-2 FT HIGHER THAN THE OFFICIAL GRIDS IN THE SW GULF WITH THE RESIDUAL SWELL BEHIND THE FRONT. BLENDING IN SOME OF THE WW3 INCREASED THE SEAS SUFFICIENTLY TO MATCH THE OBSERVATIONS. ELSEWHERE...WINDS ARE FORECAST TO INCREASE IN THE NE GULF TO A FRESH TO STRONG N BREEZE BEHIND COLD FRONT EXPECTED TO RACE THROUGH THE EASTERN GULF TONIGHT. THE 00Z ECMWF WAS SLIGHTLY FASTER THAN THE NEWER RUNS TO PUSH THE STRONGEST WINDS SOUTHWARD. THE 1520Z ASCAT-A PASS AGREES BETTER WITH THE 12Z GFS WINDS THAN THE WEAKER 00Z ECMWF BEHIND THE FRONT OFF THE SOUTH CAROLINA COAST. GRIDS WERE ADJUSTED TOWARD THE GFS AS IT WAS BETTER INITIALIZED AND CLOSER TO THE CONSENSUS THAN THE FASTER ECMWF. LARGER UNCERTAINTY COMES INTO PLAY BY WED NIGHT WHEN THE 00Z ECMWF CARRIES A DEEPER LOW PRES SYSTEM WITH STRONGER SOUTHERLY RETURN FLOW IN THE NW GULF THAN THE 12Z GFS. THE ECMWF CARRIES 30 KT WINDS HERE WHILE THE GFS AND 12Z UKMET ARE WEAKER WITH THE LOW AND THE SOUTHERLY FLOW. AGAIN...THE GRID ADJUSTMENTS SIDED WITH THE GFS WHICH SEEMS TO HAVE MORE SUPPORT FROM THE OTHER MODELS. CONFIDENCE WANES FURTHER ON THU NIGHT INTO FRI WHEN THE ECMWF DEVELOPS A LOW PRES SYSTEM INTO THE EASTERN GULF THAT THE OTHER MODELS DO NOT SHOW AND HAS VERY LITTLE SUPPORT FROM THE ENSEMBLES. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: BLEND OF GFS/WW3/NWPS GUIDANCE WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. HIGH PRES CENTERED ACROSS THE EASTERN/CENTRAL ATLC AND LOW PRES ACROSS NORTHERN COLOMBIA WILL SUPPORT MODERATE TO FRESH TRADES ACROSS MOST OF THE REGION EXCEPT THE NW CARIBBEAN THROUGH FRI... WITH A FRESH TO STRONG BREEZE EXPECTED ALONG THE COAST OF S AMERICA NEAR VENEZUELA AND COLOMBIA MAINLY IN THE OVERNIGHT HOURS. A COLD FRONT EXTENDING FROM 1011 MB LOW PRES NEAR THE WESTERN TIP OF CUBA TO THE GULF OF HONDURAS WILL WEAKEN FROM CENTRAL CUBA TO EASTERN HONDURAS TUE...AND DISSIPATE WED. WINDS ARE BELIEVED TO BE A FRESH TO STRONG BREEZE WITHIN 30 NM E SEMICIRCLE OF THE LOW WHERE CONVECTION HAS BEEN FIRING TODAY. WINDS ON THE EAST SIDE OF THE LOW SHOULD DIMINISH LATER TODAY WHILE A FRESH TO STRONG N BREEZE IS EXPECTED TO BUILD BEHIND THE FRONT THIS EVENING AS THE COLD FRONT RACING S THROUGH THE EASTERN GULF OF MEXICO BRINGS A COOL...DRY PUSH THROUGH THE YUCATAN CHANNEL. THE 12Z GFS IS STRONGER THAN THE 00Z ECMWF WITH THESE WINDS AND BETTER WITH THE STRONGER 12Z UKMET. AS EXPLAINED IN THE GULF OF MEXICO SECTION...THE GFS IS PREFERRED FOR ADJUSTING THE GRIDS WITH THIS FRONT. OTHERWISE...THE MODELS ARE IN REASONABLE AGREEMENT ON RATHER BENIGN CONDITIONS WED THROUGH FRI. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: BLEND OF GFS/WW3/NWPS GUIDANCE WITH PREVIOUS FORECAST. MEDIUM CONFIDENCE THROUGH TUE NIGHT AND LOW CONFIDENCE FROM WED THROUGH FRI NIGHT. THE SOUTHERN STREAM IS EXPECTED TO REMAIN ACTIVE THIS WEEK...WITH A SERIES OF IMPULSES FORECAST TO EJECT FROM SW TO NE ACROSS THE FORECAST AREA. 1007 MB LOW PRES ANALYZED NEAR 31N72W AT 12Z WILL SHIFT N OF THE AREA THIS AFTERNOON. A COLD FRONT EXTENDS SOUTHWESTWARD FROM THE LOW THROUGH THE CENTRAL BAHAMAS TO A SECOND LOW ANALYZED OVER THE NW CARIBBEAN NEAR 21N85W 1011 MB. THIS LOW WILL WEAKEN AT THE SURFACE AND RACE NE ALONG THE FRONTAL BOUNDARY TONIGHT AND TUE AS THE SOUTHERN STREAM TROUGH SUPPORTING THE SYSTEM PHASES WITH A NORTHERN STREAM TROUGH. A SECOND COLD FRONT ASSOCIATED WITH THE NORTHERN STREAM TROUGHING ALOFT IS MOVING INTO NW WATERS AND SHOULD QUICKLY MOVE SOUTHEAST TONIGHT AND TUE. WINDS SHOULD PICK UP TO A STRONG BREEZE BEHIND THE FRONT. AS EXPLAINED IN THE GULF OF MEXICO SECTION...THE GFS IS PREFERRED FOR ADJUSTING THE WINDS BEHIND THIS FRONT. THE MODELS GENERALLY AGREE ON THIS SCENARIO...BUT BEGIN TO DIVERGE ON WED WHEN THE NEXT SOUTHERN STREAM TROUGH BEGINS TO MOVE INTO THE AREA FROM THE GULF OF MEXICO. THE 00Z ECMWF WAS THE SLOWEST AND WEAKEST SOLUTION WITH THE ASSOCIATED SURFACE LOW AS IT PULLS E OF THE BAHAMAS ON THU. THE 00Z EC ENS MEAN IS DECIDEDLY FASTER LIKE THE MORE CONSISTENT GFS FORECAST AND THE GEFS MEAN AGREES WITH THE FASTER/STRONGER SCENARIO. THE UKMET AND GEFS SIDE WITH A SOLUTION ON THE STRONGER/FASTER SIDE OF THE GUIDANCE...BUT TRACK THE LOW ON A MORE NORTHERLY PATH THAN THE GFS. WILL HEDGE TOWARD THE GFS FOR ADJUSTING THE FORECAST...BUT WILL MAKE SOME MANUAL ADJUSTMENTS TOWARD A SLIGHTLY MORE NORTHERLY TRACK WED NIGHT THROUGH FRI. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER SCHAUER. NATIONAL HURRICANE CENTER.