000 AGXX40 KNHC 220749 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 349 AM EDT Mon May 22 2017 Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea, and Tropical North Atlantic from 07N to 19N between 55W and 64W and the Southwest North Atlantic including the Bahamas ...GULF OF MEXICO... Weak high pressure ridging extends from the SW Atlantic to near the Mississippi Delta. A frontal boundary is stalling along the Texas and Louisiana Coasts. The boundary is providing the focus for deep convection along the Texas and Louisiana Coasts. Have added wording for winds and seas higher this morning in and near this convection N of 27N for zones GMZ011 and GMZ013. Winds are otherwise light to moderate over the northern half of the Gulf near the ridge axis. Over the southern half of the Gulf winds are moderate to fresh. Fresh NE to E winds are occurring over the Bay of Campeche just to the NW of the Yucatan Peninsula as a thermal trough moves W. Latest buoy observations and recent altimeter data show seas ranging 3-5 ft over the Gulf. Seas could briefly reach 7 ft early this morning within the area of convection over the NW Gulf. As the ridge shifts SE today through Wednesday in response to the weak frontal boundary that is stalling and beginning to weaken along the Northern Gulf Coast, winds over the Gulf will generally remain gentle to moderate. Convection associated with the front will be decreasing as the front loses identity. A stronger cold front supported by an upper-level trough is progged by the global models to enter the NW Gulf late Tuesday night. SW winds ahead of the front will remain light to moderate due to the weak ridging ahead of the front. The front should reach from the NE Gulf to the NW Yucatan Peninsula Wednesday night, and from South Florida to the Bay of Campeche by Thursday evening as it weakens. High pressure building in behind the front will be rather weak. This will provide for light to moderate northerly winds in the wake of the front Wednesday through Thursday, with the exception of moderate to fresh winds over the NE Gulf. Seas before and after frontal passage should remain in the 3-6 ft range. Seas ahead of the front could peak around 7 ft in the NE corner of zone GMZ015 on Wednesday. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... The monsoon trough reaches E from the NE Pacific to the NW coast of Colombia. Showers and thunderstorms associated with the trough have diminished for the time being. However, this activity is likely to flare up again during next several days with model guidance suggesting the formation of a broad area of low pressure within the monsoon trough over the NE Pacific towards the end of this week. Winds over the Caribbean have begun to diminish as the ridge over the NW Atlc weakens in response to low pressure moving eastward from the Eastern United States. Satellite-derived wind data show winds are moderate to fresh...except for a narrow band of fresh to strong NE to E winds over the Gulf of Venezuela and along the N Coast of Colombia. Buoy reports indicate 3 to 7 ft seas in the Caribbean. The pressure gradient over the Caribbean will tighten again on Wednesday as central Atlantic high pressure builds W. A tropical wave arriving from the Tropical N Atlantic is expected to bring a surge of increasing trades across much of the Caribbean. Seas could build to 10 or 11 ft over the central Caribbean Thursday through Friday, then begin to subside Friday night. A brief round of NE to E swell will produce a small area of 8-ft combined seas over the southern sections of the Tropical N Atlantic zones beginning this afternoon. This area will decay by Tuesday evening. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A 1021 mb high is centered W of Bermuda at 31N71W. The high ridges westward over the SE U.S. A surface trough curves NE from 20N63W to 27N52W. Satellite imagery shows this feature is supported by an upper-level low. Scattered showers and thunderstorms associated with this trough remain east of the forecast zones from 25N to 27N between 52W and 55W. The high is maintaining gentle to moderate E to SE winds north of 22N and moderate to fresh E winds south of 22N. The strongest winds will continue near the approaches to the Windward Passage today, then diminish on Monday and Tuesday as the ridge weakens and shifts ESE. Winds will increase and veer from the south over the NW waters beginning on Wednesday in advance of a cold front. The front will 31N81W late Wednesday night, move over the NW waters of the basin Thursday and Thursday night, then across the north- central waters N and NE of the Bahamas late Thursday night through Friday evening as it weakens. The front will primarily affect zones AMZ111 and AMZ115. Model guidance continues to call for fresh to strong SW winds preceding the front and accompanying seas of 7-10 ft. Seas will be highest near 31N. Winds and seas associated with the front will decrease and lift N of 31N Thursday night through Friday night as weak high pressure builds E from Florida. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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.nhc.noaa.gov/marine $$ .Forecaster McElroy. National Hurricane Center.