000 AGXX40 KNHC 210813 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 413 AM EDT Sat Oct 21 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... A surface ridge cuts across the area along a line from the FL Panhandle to the NE tip of the Yucatan Peninsula. The wind speeds from 90W eastward are in the range from moderate to fresh. Moderate wind speeds cover the area that is from 28N southward from 95W westward, from Texas to Mexico. Fresh-to-strong winds are being observed in scatterometer data from 25N northward from 90W eastward. Altimeter data from 20/1500 UTC were showing 8 foot sea heights in the north central sections, from 25N northward between 90W and 93W. The pass for altimeter data for 21/0300 UTC did give any data in that same area. Sea heights range from 3 feet to 6 feet in other areas. High pressure in the SE USA will move slowly eastward into the Atlc through the weekend. Expect fresh E winds to continue in at least the NE corner of the area on Saturday. Winds veer and subside briefly Sun before increasing again Mon, ahead of a cold front that is forecast to move off the Texas coast on Sun during the middle of the morning, and then rapidly across the northern Gulf, extending from near Mobile, AL to the waters that are just off the western part of the Yucatan Peninsula by Mon sunrise; from NE FL toward NW Cuba by Tue sunrise; and clearing the Gulf by Wed sunrise. The GFS/ECMWF/NAM models appeared to have the best handle on the timing of the front. Expect Northerly 20 to 25 knot winds and some 8 foot sea heights, in the SW corner of the area, from 24N southward from 94W eastward, from Monday sunrise until at least Wednesday around noon. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... Two tropical waves will continue across the western sections of the Caribbean Sea tonight, and across the western sections and parts of Central America on Saturday, Sunday, and Monday. E to ESE trades of 20-25 KT with 7-11 FT seas prevail across the basin S of 18N W of 64W until Tuesday midnight. The wind speeds will diminish across the rest of the basin late Mon and Tue as broad low pressure takes shape in the far SW Caribbean late Tue and early Wed, just as a cold front enters the far NW corner of the Caribbean Sea Tue Night and Wed. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A stationary front passes through 27N65W to 26N70W to 26N75W. A surface trough is along 25N76W, across Cuba, to 20N78W. Isolated moderate rainshowers are from 24N northward between 65W and 72W. NE mostly 20 knot winds, and possibly some 25 knot winds, are part of the scatterometer data that show up from 25N to 28N between 73W and 78W. Rapidly developing low pressure well N of the area will move the front eastward more and more through Sat. The surface pressure gradient that is to the south of the high pressure that is in the N Atlantic will maintain fresh trades to the W of 70W with winds of 20-25 KT pulsing N of Cuba and Hispaniola tonight through Sun night. Winds in the NW waters veer to the SE and increase to 20 to locally 30 KT late Mon and early Tue, ahead of a cold front that is forecast to move off the SE Coast after sunset on Tuesday night. The cold front passes through 31N74W 27N75W 22N78W after sunset on Wednesday night; through 31N68W 25N70W 20N71W after sunset on Thursday; and then to the east of the area during Friday. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 MT. National Hurricane Center.