000 AXNT20 KNHC 200600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 200 AM EDT Thu Jun 20 2019 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0520 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: The pressure gradient between the Atlantic ridge and the Colombian low will support minimal gale force winds tonight in the Gulf of Venezuela and off the north coast of Colombia. Winds will then be just below gale force Thu morning until late Friday, when gales are again expected off the coast of Colombia. Seas of 12-16 ft are expected across the south-central Caribbean, including the Gulf of Venezuela, tonight. See the latest NWS High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers HSFAT2/FZNT02 KNHC, or at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for further details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 34W S of 13N. A moisture maximum in the LPW is noted near this wave. Scattered showers are seen near this wave from 08N- 09N between 32W-35W. A Caribbean Sea tropical wave is along 64W S of 16N. Scattered thunderstorms and showers are seen within the vicinity of this wave from 14N-15N between 63W-67W. A Caribbean Sea tropical wave is along 76W S of 18N. Due to dry Saharan air, little to no convection is noted. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea- Bissau near 12N16W to 08N20W. The ITCZ continues from 08N20W to 07N32W, then continues W of a tropical wave near 06N36W to the coast of Brazil near 05N53W. Scattered moderate convection is seen along the ITCZ and south of the monsoon trough from 05N-10N between 18W-56W. A well defined line of thunderstorms is moving off of Guinea and Sierra Leone from 09N-10N between 13W-16W. GULF OF MEXICO... An upper-level trough continues to dig across Florida, with mid- upper level ridging covering the western Gulf. Scattered showers with isolated thunderstorms are seen just off the coast of Florida, however most of the significant convection has dissipated. Fair weather prevails across the central and western basin. Gentle to moderate anticyclonic winds prevail in the central and eastern Gulf with moderate easterly winds north of the Yucatan. Moderate southeasterly winds are in the western Gulf particularly off the Texas and Mexican coast W of 96W. A diurnal trough forming over the Yucatan Peninsula will produce fresh to strong winds each night as it moves NW into the SW Gulf of Mexico. Otherwise, a high pressure ridge will slowly move northward over the Gulf through the weekend, then persist over the NE Gulf through Monday night. CARIBBEAN SEA... See the special features section in regards to the Caribbean Gale warning. Two tropical waves are traversing the Caribbean Sea. See the Tropical Waves section above for details. The upper level pattern consists of a shortwave trough across the NW Caribbean Sea and a weak upper ridge over the central and eastern Caribbean. The GOES-16 Saharan Air Layer tracking product shows that a plume of African dust has reached the western and central Caribbean Sea. Strong subsidence is keeping convection at a minimum, with some isolated thunderstorms adjacent to the monsoon trough moving off the coasts of Panama and Costa Rica, S of 10N between 76W-82W. The latest ASCAT pass shows gale force winds in the Gulf of Venezuela and north of Colombia, with fresh strong winds throughout the central Caribbean. Fresh to strong winds are also noted in the Bay of Honduras. Moderate trades are seen in the eastern basin, with gentle to moderate trades in the northern Caribbean. The pressure gradient between Bermuda high pressure and the Colombian low will support nocturnal pulsing of minimal gale force winds off the coasts of Colombia and Venezuela through Saturday night, except on Thursday night. Strong winds are expected to pulse in the Gulf of Honduras each night through Sunday night. A tropical wave near 64W will produce scattered thunderstorms with gusty winds as it moves westward across the central and western Caribbean Thursday through Saturday. Elsewhere, generally moderate to fresh trades will prevail through the weekend and into early next week. ATLANTIC OCEAN... The convection from earlier in the western Atlantic has weakened with showers and isolated thunderstorms seen from 27N30N between 75W-79W. The GOES-16 Saharan Air Layer tracking product shows that a plume of African dust extends from Puerto Rico to the Central Bahamas, including Hispaniola and eastern and central Cuba. Otherwise, fair weather prevails across the rest of the basin as surface ridging from a 1024 mb high near 27N50W dominates the area. Light anticyclonic winds are seen across most of this area, with moderate to fresh southwesterly winds in the western Atlantic. Moderate to fresh winds are also noted across the Atlantic S of 20N. Strong winds will pulse north of Hispaniola tonight and Thursday night. Winds will strengthen over the northern waters Thursday through Friday ahead of a cold front that will move off the U.S. East Coast late in the week. A high pressure ridge will dominate much of the region through Saturday, then weaken Sunday into Monday as the cold front continues moving across the western Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ AKR