000 AGXX40 KNHC 081857 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 257 PM EDT TUE SEP 8 2015 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: USED LATEST GFS AND MWW3 BLEND WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. A RATHER NARROW MID/UPPER LEVEL CYCLONIC CIRCULATION IS NEAR 27N90W WITH A TROUGH EXTENDING SW TO THE BAY OF CAMPECHE AND NE TO TO THE MOUTH OF THE MISSISSIPPI RIVER. ASSOCIATED SCATTERED SHOWERS AND TSTMS ARE CONCENTRATED OVER THE CENTRAL GULF FROM 22N-26N BETWEEN 85W-94W. A 1013 MB LOW MOVED INLAND THE FLORIDA PANHANDLE THIS MORNING. A WEAK PRES PATTERN IS PRESENT ACROSS THE AREA. LATEST BUOY OBSERVATIONS ARE REPORTING GENERALLY GENTLE WINDS THROUGHOUT WITH WIND DIRECTION IN CYCLONIC FORM OVER THE EASTERN GULF. SEAS REMAIN RELATIVELY LOW...IN THE 1-2 FT RANGE. ATLC HIGH PRES WILL BEGIN TO BUILD WESTWARD ACROSS THE AREA ALONG 27N BEGINNING TONIGHT...AND CHANGE LITTLE THROUGH SUN. SEAS WILL REMAIN IN THE 1-2 FT RANGE. AN INVERTED THERMAL TROUGH WILL DEVELOP EACH AFTERNOON OVER THE YUCATAN PENINSULA...AND THEN MOVE WNW ACROSS THE SW GULF WATERS...GENERALLY TO THE S OF 22N BETWEEN 90-93W DURING THE EVENING THROUGH LATE NIGHT HOURS...REACHING ALONG 94-95W DURING THE EARLY DAYLIGHT HOURS...AND THEN DISSIPATING BY EARLY AFTERNOON. EXPECT THIS TROUGH TO BE ACCOMPANIED BY A NE-E 10-15 KT NOCTURNAL EVENTS THROUGH WED NIGHT...THEN GUIDANCE SUGGESTS WINDS INCREASING TO 15-20 KT AT NIGHT BEGINNING ON WED. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: USED LATEST GFS AND MWW3 BLEND WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. THE ATLC RIDGE N OF THE AREA COMBINED WITH LOW PRESSURE OVER NW COLOMBIA WILL CONTINUE TO ENHANCE FRESH TRADES ACROSS THE THE S- CENTRAL WATERS...EXCEPT INCREASING TO STRONG WITHIN ABOUT 180 NM OF THE COLOMBIAN COAST EACH NIGHT THROUGH WED NIGHT WITH THESE CONDITIONS CONTINUING INTO THE EARLY MORNING HOURS OF THU RESULTING IN COMBINED SEAS OF ABOUT 8-11 FT ON WED. SEAS ARE FORECAST TO SUBSIDE 5-8 FT BY LATE THU AND TO 4-5 FT BY SAT AS THE CULPRIT PRESSURE GRADIENT RELAXES. A TROPICAL WAVE OVER THE WESTERN CARIBBEAN NEAR 80W MOVING W AT 10-15 KT. SCATTERED SHOWERS AND TSTMS ARE AHEAD OF THE WAVE FROM 16N-20N BETWEEN THE WAVE AND 82W. THIS WAVE WILL MOVE THROUGH THE REST OF THE WESTERN CARIBBEAN TONIGHT INTO WED. ANOTHER WAVE NEAR 66W IS MOVING W AT 15 KT. THIS WAVE WAS AGAIN NICELY CAPTURED BY THE 1424 UTC ASCAT PASS FROM THIS MORNING WHERE IT CLEARLY SHOWED THE NE TO SE WIND SHIFT. SATELLITE IMAGERY IS SHOWING SCATTERED TO NUMEROUS SHOWERS AND TSTMS WITH GUSTY WINDS RACING OUT AHEAD OF THE WAVE TO NEAR 68W AND S OF 13N. THIS WAVE WILL MOVE ACROSS THE REST OF THE EASTERN CARIBBEAN DURING THE REMAINDER OF THE AFTERNOON...AND ACROSS THE CENTRAL CARIBBEAN TONIGHT AND WED...AND ACROSS THE WESTERN CARIBBEAN FRI THROUGH SAT. CONDITIONS ASSOCIATED WITH THE WEAKENING REMNANT LOW OF TROPICAL STORM GRACE WILL ARRIVE NEAR 15N55W LATE WED NIGHT...REACH THE LEEWARD ISLANDS ON FRI...AND MOVE ACROSS PUERTO RICO AND ITS VICINITY FRI NIGHT BEFORE WEAKENING FURTHER TO A TROPICAL WAVE SAT THROUGH SUN AS MOVES OFF TO THE NW OF PUERTO RICO AND TOWARDS THE SE BAHAMAS TO HISPANIOLA WATERS WITH WINDS AT THAT TIME IN THE RANGE OF ABOUT 20-25 KT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS AND MWW3 BLEND WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. STILL THE MAIN FEATURE IS THE RIDGE THAT EXTENDS NEAR 26N E OF THE NW BAHAMAS AS DEFINED IN THE 1424 ASCAT PASS WINDS AND IN LOW CLOUD OBSERVED MOTION. A WEAK SURFACE TROUGH IS JUST NW OF THE AREA OVER NE FLORIDA EXTENDING TO THE NE GULF. SEAS REMAIN RATHER LOW...IN THE 2-3 FT RANGE E OF THE BAHAMAS AND 1-2 FT W OF THE BAHAMAS. LITTLE OVERALL CHANGES ARE EXPECTED WITH THE CURRENT FORECAST INTO DAY 5 (SUN). LOW PRESSURE E OF THE AREA NEAR 31N64W WILL REMAIN NEARLY STATIONARY THROUGH WED AFTERNOON...THEN MOVE SLOWLY NORTHWARD WITH THE POSSIBILITY OF IT BECOMING A TROPICAL CYCLONE. THE LOW WILL DRAG A WEAK COLD FRONT ACROSS THE WATERS N OF 27N E OF 70W. WINDS WILL REMAIN IN THE RATHER GENTLE RANGE WITH SEAS LITTLE CHANGES TO THE CURRENT OBSERVED SEAS OF 1-3 FT. THE ELY TRADES WILL INCREASE TO 15-20 KT ACROSS THE TROPICS WELL E OF THE LEEWARDS...NEAR 20N56W BEGINNING ON THU NIGHT IN ADVANCE OF THE REMNANTS OF TROPICAL STORM GRACE WHICH WILL REACH THE VIRGIN ISLAND AREA LATE FRI NIGHT..THESE 15-20 KT CONDITIONS WILL SPREAD N ACROSS THE TROPICS S OF 22N BETWEEN 65W AND 72W ON SAT. THE REMNANTS SHOULD WEAKEN TO A TROPICAL WAVE AS IT MOVES ACROSS THE WATERS FROM NEAR PUERTO RICO TO THE BETWEEN HISPANIOLA AND THE SE BAHAMAS SAT THROUGH SUN. EXPECT WINDS SHIFTING FROM NE-SE AT 20-25 KT WITH THE WAVE WITH SEAS OF 8-9 FT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 AGUIRRE. NATIONAL HURRICANE CENTER.