000 AGXX40 KNHC 221735 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 135 PM EDT FRI APR 22 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. MODEL PREFERENCE: BLEND OF THE 12Z GFS WITH PREVIOUS OFFICIAL WIND FORECAST THROUGH SUN THEN 00Z/22 ECMWF ADDED. OFFICIAL WAVE FORECAST BLENDED WITH 12Z NWPS. HIGH CONFIDENCE. WINDS ACROSS THE GULF OF MEXICO ARE EXPECTED TO REMAIN BELOW THE ADVISORY CRITERIA OF 20-25 KT ACROSS THE BASIN THROUGH TUE NIGHT. THE 12Z GFS AND 00Z/22 ECMWF ARE IN REASONABLE AGREEMENT WITH THE TIMING OF THE COLD FRONT EXPECTED TO PASS THROUGH THE NE HALF OF THE GULF TODAY THROUGH SAT...AND THERE IS GENERAL AGREEMENT ON HIGH PRES MIGRATING E THROUGH THE N GULF OVER THE WEEKEND. THE GFS SOLUTION LOOKS REASONABLE FOR ADJUSTING THE GRIDS THROUGH THAT TIME. SOME DIFFERENCES ARISE IN THE NORTHERN STREAM BY MON THAT INFLUENCE THE PRES GRADIENT ACROSS THE W GULF. THE MODELS GENERALLY AGREE ON A TIGHTENING OF THE GRADIENT AND STRONGER SE WINDS EARLY NEXT WEEK HERE AS TROUGHING BUILDS OVER TEXAS. WHILE UNCERTAINTY INCREASES SLIGHTLY AT THIS POINT IN THE FORECAST...THE MODELS ARE KEEPING WINDS UNDER THE ADVISORY CRITERIA THROUGH THE END OF THE PERIOD TUE NIGHT. A BLEND OF THE GFS AND ECMWF WAS USED TO ADJUST THE GRIDS TO ALLEVIATE SOME OF THE UNCERTAINTY IN THE DETAILS. THE 12Z NWPS INCORPORATES THIS THINKING. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: BLEND OF THE 12Z GFS WITH PREVIOUS OFFICIAL WIND FORECAST THROUGH SUN THEN 00Z/22 ECMWF ADDED. OFFICIAL WAVE FORECAST BLENDED WITH 12Z NWPS...WITH THE 00Z/22 EC WAVE ADDED IN THE TROPICAL ATLC. MEDIUM CONFIDENCE. THE PRES GRADIENT WEAKEN ACROSS THE N CENTRAL CARIBBEAN THROUGH TONIGHT AS STRONG HIGH PRES CURRENTLY PASSING S OF BERMUDA WEAKENS AND MOVES SOUTHEASTWARD. WINDS WILL BEGIN TO SHRINK TO ALONG THE COAST OF COLOMBIA/VENEZUELA SAT AS THE HIGH PULLS AWAY. WINDS WILL DIMINISH BELOW ADVISORY CRITERIA BY OVERNIGHT SAT NIGHT. THE GFS IS IN GOOD AGREEMENT WITH THE GLOBAL MODEL MEAN WITH THIS SCENARIO AND GENERALLY HANDLES THE OROGRAPHIC ENHANCEMENTS BEST. IT WAS USED TO ADJUST THE GRIDS THROUGH SUN. IN THE TROPICAL ATLC...A NEW ROUND OF NORTHERLY SWELL IS MOVING INTO THE AREA AND SHOULD BRING SEAS TO NEAR 8 FT TONIGHT THROUGH THE WEEKEND. THE EC WAVE GENERALLY HANDLES LONG-PERIOD SWELL IN THE OPEN ATLC WATERS BETTER THAN THE NWPS AND MWW3...SO IT WAS ADDED TO THE BLEND. BY MON...THE GLOBAL MODEL CONSENSUS SIDES MORE TOWARD THE STRONGER ECMWF WITH THE LOW PRES SYSTEM PASSING SE FROM BERMUDA THROUGH THE CENTRAL ATLC. THE ECMWF WAS ADDED TO THE BLEND TO ADJUST THE WIND FORECAST MON AND TUE...AND THE EC WAVE COMPONENT WAS INCREASED ACROSS THE ENTIRE AREA. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: BLEND OF THE 12Z GFS WITH PREVIOUS OFFICIAL WIND FORECAST THROUGH SUN THEN 00Z/22 ECMWF ADDED. OFFICIAL WAVE FORECAST BLENDED WITH 12Z NWPS AND THE 00Z/22 EC WAVE. MEDIUM CONFIDENCE. HIGH PRES N OF THE AREA IS FORECAST TO WEAKEN AS IT MOVES FROM NE WATERS SOUTHEASTWARD AWAY FROM THE AREA TONIGHT THROUGH THE WEEKEND. THE MODELS ARE IN REASONABLY GOOD AGREEMENT ON THIS SCENARIO AND HAVE COME INTO BETTER AGREEMENT WITH THE TROUGHING EXPECTED TO BUILD OVER W WATERS TONIGHT AND SAT. AS STATED IN THE GULF OF MEXICO SECTION...THE 12Z GFS WAS PREFERRED WITH THE WEAK COLD FRONT MOVING ACROSS THE NORTHERN GULF AND ENTERING NW WATERS IN THE SW N ATLC EARLY SAT. THE MODELS AGREE ON DEVELOPING WEAK SURFACE LOW ALONG THE FRONT N OF THE AREA SAT NIGHT AND SEND IT EASTWARD THROUGH BERMUDA SUN NIGHT. THE MODELS BEGIN TO SHOW SIGNIFICANT DIFFERENCE BY MON AS A SECONDARY COLD FRONT MOVES INTO THE N WATERS AND PASSES SOUTHEASTWARD BEHIND THE PRIMARY FRONT. THE 00Z/22 ECMWF LOOKS MORE LIKE THE MODEL CONSENSUS BY THIS TIME...CARRYING A STRONGER SECONDARY FRONT AND GENERALLY BECOMING MORE AMPLIFIED WITH THE PATTERN THAN THE 12Z GFS. THE GFS IS TRENDING TOWARD THE ECMWF SOLUTION HERE. THE ECMWF WAS USED TO ADJUST THE GRIDS MON AND TUE. A BLEND OF THE 12Z NWPS AND 00Z/22 EC WAVE WAS PREFERRED FOR THE SEAS...AS THE ECMWF FORECAST IS PREFERRED FOR ADJUSTING WINDS AND THE EC WAVE GENERALLY HANDLES LONG-PERIOD SWELL IN THE OPEN ATLC WATERS BETTER THAN THE NWPS AND MWW3. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.