000 AGXX40 KNHC 111033 MIMATS Marine Weather Discussion...UPDATED NWS National Hurricane Center Miami FL 533 AM EST Sat Feb 11 2017 updated to include mention of fog in NW Gulf of Mexico 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... MODEL PREFERENCE: Global model consensus. High Confidence. A high center of 1029 mb over the western Atlantic east of NE Fl extends a ridge westward across the northern portion of the area. The associated gradient is supporting fresh east to southeast winds over the southeastern gulf, including the Straits of Fl. Ascat data from 0336Z last night along with the current buoy and satellite-derived winds observations show generally moderate to fresh southerly winds over the western waters and mainly moderate southeast to south winds elsewhere. The buoy observations along with recent altimeter data reveal seas in the 4-6 ft range, except for a patch of higher seas in the range of 5-7 ft in the eastern gulf from 22N to 27N between 83W-87W, and in the Straits of Fl. Lower seas of 2-3 ft are confined to the far northeast and north-central waters as well as to the southwest of a line from northeast Mexico to the northwest Yucatan peninsula. Patchy fog over portions of the northwest gulf as seen in satellite imagery, and as being reported by platform sites there is due to moist southerly flow over the cooler shelf waters. The fog is expected to dissipate late this morning, and may possibly form again tonight. Global models are in very good agreement that the ridge will shift southeastward while weakening through Sunday night as a weak cold front drops southward to along the northern gulf coastal plains. The front will become diffuse during Monday over the northern gulf waters as a large area of strong high pressure surges southward across the the front and to the central waters through Monday night. The high pressure will weaken and shift eastward through Tuesday allowing for a stronger cold front to move offshore the Tx coast Tuesday evening. This front will push across the northwest gulf Tuesday night into Wednesday, the central and northeast waters Thursday and across the eastern waters Thursday night. The models have come more into agreement with this scenario, although differences with timing of the front across the area are still noted. Will lean towards the slower envelop of the models for the progression of the front across the gulf for this package. The front will be followed by strong northwest to north winds. Max seas building to around 9 or 10 ft in the western gulf are expected Wednesday and Wednesday night, with seas of 5-8 ft expected elsewhere behind the front. Wave model guidance depicts seas lowering rather quickly throughout Thursday and Thursday night as the gradient in the wake of the front rapidly slackens. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: Global model consensus. High Confidence. The pressure gradient between subtropical high pressure passing north of the region and the climatological low pressure residing over Colombia will support persistent fresh to strong trades over the south central Caribbean through the forecast period. The gradient has again tightened tonight as seen in the 0152Z Ascat pass, and will do so again Sunday night to allow for northeast to east winds to pulse to gale force within about 90 nm of the coast of Colombia. Latest wave guidance provided seas in the range of 10-14 ft for this morning, and 9-13 ft for Sunday night with these winds. The winds will not be as strong Monday and Tuesday as the ridge to the north of the area over the western Atlantic weakens while shifting eastward. The front that entered the northwest Caribbean yesterday has dissipated, with the tail-end of the front analyzed over eastern Cuba as of 06Z. This portion of the front will stall later today, and gradually wash out through Sunday. High pressure over the eastern United States will support fresh to strong northeast winds over the northwest Caribbean through Sunday morning, with the strongest winds over the Lee of Cuba and Windward Passage. Seas will build to near 8 ft with the stronger wind fetches. The high will weaken early next week, which will result in winds diminishing to 10-15 kt over much of the Caribbean. E swell producing seas of 7-9 ft in the southern portion of the tropical N Atlantic zones will decay through this evening allowing for these seas to subside slightly, then subside further on Sunday with seas lowering to 5-7 ft. However, a batch of northerly swell generated by a frontal system to the north of the region will produce seas up to the range of 7-10 ft in zone AMZ127 tonight and Sunday, and also to zone AMZ027 on Sunday. The swell energy will be dissipating on Sunday. The seas in zone AMZ027 are expected to be about 6-8 ft before subsiding to 5-7 ft on Monday, and 4-5 ft all tropical N Atlantic zones on Tuesday. Yet another set of northerly swell is expected to arrive into the far northern portion of zone AMZ127 on Wednesday upping the seas there to 8-10 ft. This northerly swell will then propagate through zone AMZ027 and the through much of zone AMZ037 late Wednesday night through Thursday with seas of 7-9 ft. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: Global model consensus. High Confidence. The 06Z surface analysis has a cold front now over the southeast waters along a position from 23N65W to eastern Cuba. A pre- frontal trough is analyzed within 90 nm southeast of the front. A 1029 mb high pressure center is near 30N73W. This feature is controlling the wind regime throughout as both current buoy observations and Ascat data from last night depict anticyclonic flow across the basin. The tighter pressure gradient between the front and the high pressure has induced fresh to occasional strong northeast winds northwest of the front to a line from 26N65W to 24N72W to the Straits of Fl. Fresh to strong northeast winds are noted in the 0154Z Ascat pass to be present through the windward passage. In addition, a couple of recent ship observations also revealed similar winds at the entrance of the passage. Recent altimeter data and the sea state analysis from 00Z last night revealed seas in the range of 10-15 ft north of 25N east of 74W, and 8-12 ft elsewhere northeast of the Bahamas. Seas to the southeast of the front are in the 5-7 ft range, and 6-8 ft remainder of forecast area, with the exception of lower seas of 2-3 ft in the vicinity of the Bahamas, and 5-7 ft west of the Bahamas and Straits of Fl. As advertised in previous forecasts, the cold front will lose all of its upper support and become stationary near its present location later today and through Sunday before dissipating Sunday night. The fresh to strong northeast winds behind the front will diminish Sunday, with just fresh northeast confined to the windward passage and its entrance. The large swell producing the high seas northeast of the Bahamas will gradually decay through Sunday as it propagates southeastward to the far southeast waters and the northern sections of the tropical N Atlantic zones. Seas will respond by lowering below 8 ft all zones, except in zones AMZ121, AMZ125 and AMZ127 where seas will be in the 7-9 ft range. These seas then lower to 5-7 ft on Monday as high pressure settles in over the area temporarily. On Monday, a new cold front will cross the northern zones with fresh to strong winds entering the area mainly north of 27N, with another area of large swell of 9-14 ft propagating into the TAFB northeast offshore waters. On Tuesday, the swell continues to build seas with wave model guidance indicating a maximum of 16 ft in the northeast portion of zone AMZ115. By Wednesday, the guidance indicates seas lowering to 9-10 ft, but are expected to cover a good portion of the eastern zones. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... Gale Warning till 15Z this morning and again tonight. Gale Warning Sun night. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Aguirre. National Hurricane Center.