000 AGXX40 KNHC 190756 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 356 AM EDT Mon Jun 19 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... High pressure prevails over the Gulf waters. Latest satellite derived winds and seas along with ship, buoy, and CMAN data depict light to gentle winds over the northeast Gulf, fresh to locally strong winds over the far southeast Gulf, and gentle to moderate winds over the remainder of the Gulf waters. Seas are in the 1-2 ft range over the northeastern Gulf, 4-5 ft over the northwest Gulf, 7-10 ft over the southeast Gulf, and 2-3 ft over the southwest Gulf. A large cyclonic gyre prevails over the northwest Caribbean and Central America. There remains considerable uncertainty with the overall structure, strength, and location of the feature over the Gulf waters as the forecast evolves into early to middle part of the week. Presently, there appears to be a rather ill- defined cyclonic circulation associated with the gyre just inland the east coast of the Yucatan peninsula, with a surface trough extending northeastward to the NE Gulf. Will maintain continuity with previous forecast packages in keeping a general northwest track with this system through the next 48 hours, then wil be forecast it to track more in a northwest to north motion thereafter as it responds to a weakens in the Atlantic ridge to the east. approaches the coast. Low confidence remains with respect to this evolving scenario, and will updated forecast and NDFD grids accordingly in the future as needed. There remains a high chance that this low will develop into a tropical cyclone over the next couple of days. Regardless of tropical cyclone development, this system will impact the area with strong winds, with southerly winds to gale force over portions of the offshore waters of the eastern gulf in tight gradient present there to the east of the low and trough along with building seas likely over much of the central and eastern Gulf through much of Wednesday. Very active and widespread showers and thunderstorms will accompany this system. The rainfall associated to this system will also impact portions of Central America, the Yucatan Peninsula, and western Cuba with flash flooding and mudslides possible over prone areas. Interests in the southern Gulf, and surrounding land masses, should monitor the Tropical Weather Outlook for the latest information on this evolving weather scenario. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A Central American Gyre prevails over the northwest Caribbean waters and Central America with active convection prevailing over the northwest waters. ASCAT data from during the day yesterday showed gale force southerly winds over the waters south of western Cuba. These winds are forecast to lift north of the Caribbean by late this morning. Elsewhere fresh to strong winds prevail over the northern waters south of eastern Cuba and Jamaica, fresh winds elsewhere over the Central Caribbean, and moderate to fresh winds over the remainder of the forecast waters. The gyre will continue to bring widespread showers and thunderstorms to much of the NW Caribbean until around mid-week. The rainfall associated to this system will also impact portions of Central America, the Yucatan Peninsula, and western Cuba, with flash flooding and mudslides possible over prone areas. The latest buoy and altimeter observations reveal seas in the 8-10 ft range south of central Cuba, except for higher seas of 10-14 ft north of about 19N and west of 84W. These seas will gradually diminish through early on Tuesday. Elsewhere, seas are in the 6-8 ft range over the central Caribbean, 4-6 ft over the remainder of the Caribbean waters, and 7-11 ft over the tropical north Atlantic forecast zones, with the exception of much higher seas described below in association with potential tropical cyclone TWO. The strong low that was along a tropical wave the past few days moving quickly westward has become potential tropical cyclone TWO as of Sunday afternoon with maximum winds of 35 kt with gusts to 45 kt. The latest NHC advisory issued at 0600Z has the center of this system near 8.3N 53.5W maintaining 35 kt with gusts to 45 kt and minimum pressure of 1005 mb and moving westward at 20 kt. This potential tropical cyclone is forecast by the latest NHC advisory valid at 03Z to move across the far southern waters of the tropical N Atlantic zones through tonight, then across the far southeast Caribbean Sea through Tuesday night while it gradually begins to weaken eventually reaching post-tropical/remnant low status over the far south- central Caribbean by late Wednesday. The remaining entity appears will be a tropical wave that will move across the rest of the Caribbean through Thursday while dampening out. A long easterly fetch north of the system will allow for combined seas to build to maximum of about 15 ft within about 90 nm of the center in the northern semicircle before crossing the lower Windwards islands late tonight. These seas will slowly lower to 12 ft over the southeast Caribbean, and to just below 12 ft by late Wednesday as it weakens over the far south-central Caribbean Sea as it weakens. Otherwise, high pressure over the western Atlantic will support increasing trade winds and building seas over much of the central and eastern Caribbean during much of the forecast period, with only a diminishing area of strong southeast winds expected over the Gulf of Honduras Zone 017 by late Thursday night. ...SW N ATLANTIC INCLUDING THE BAHAMAS... High pressure prevails over the forecast waters. Latest satellite derived winds and seas along with ship, buoy, and CMAN data depict moderate to fresh winds over the southern waters with light to gentle winds over the northern waters. Seas are in the 3-4 ft range outside the Bahamas except for slightly higher seas of 4-6 ft seas south of about 22N, and seas of 1-2 ft west of the Bahamas. High pressure will prevail over the forecast waters through Wednesday night before it begins to lift north and weaken some Thursday through Friday night. Fresh to locally strong east to southeast winds will prevail over the southwest waters before diminishing during Wednesday, however, east winds will continue to pulse starting in the afternoons and into the following mornings between Hispaniola and the SE Bahamas through Friday. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... GMZ015...NE GULF N OF 25N E OF 87W... Gale Warning S of 27N today into Tue. .GMZ019...CENTRAL GULF FROM 22N TO 26N BETWEEN 87W AND 94W... Gale Warning E of 87W tonight. .GMZ021...E GULF FROM 22N TO 25N E OF 87W INCLUDING STRAITS OF FLORIDA... Gale Warning W of 85W today into tonight. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ013...CARIBBEAN N OF 18N BETWEEN 76W AND 85W INCLUDING CAYMAN BASIN... Gale Warning early today. .AMZ033...CARIBBEAN S OF 15N BETWEEN 64W AND 72W INCLUDING VENEZUELA BASIN... Tropical Storm Warning Tue into Tue night. .AMZ035...OFFSHORE WATERS WINDWARD ISLANDS INCLUDING TRINIDAD AND TOBAGO... Tropical Storm Warning tonight into Tue. .AMZ037...TROPICAL N ATLANTIC FROM 07N TO 15N BETWEEN 55W AND 65W... Tropical Storm Warning today into tonight. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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.