000 AXNT20 KNHC 201057 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 657 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 0600 UTC surface analysis and satellite imagery through 1019 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: The pressure gradient between the Atlantic ridge and the Colombian low will support minimal gale force winds in the Gulf of Venezuela and off the north coast of Colombia until 1200 UTC this morning. Winds will then be just below gale force Thursday morning until late Friday, when gales expected to return off the coast of Colombia. Seas of 11-17 ft are expected across the south- central Caribbean. 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 36W S of 12N. A moisture maximum in the LPW is noted near this wave. Scattered showers are seen near this wave from 06N- 09N between 34W-37W. A Caribbean Sea tropical wave is along 65W S of 15N. Scattered moderate convection is seen within the northern vicinity of the wave from 14N-16N between 64W-69W. A Caribbean Sea tropical wave is along 78W S of 16N. Due to dry Saharan air, little to no convection is noted. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea near 10N14W to 08N23W. The ITCZ continues from 08N23W to 08N32W, then continues W of a tropical wave near 07N37W to the coast of Brazil near 04N51W. Scattered showers are moving along the monsoon trough from 09N-10N between 14W-16W. Scattered showers with isolated thunderstorms are seen south of the monsoon trough and along the ITCZ from 05N- 10N between 18W- 38W, with another area of scattered showers and isolated thunderstorms along the ITCZ from 03N-07N between 45W- 52W. GULF OF MEXICO... An upper-level trough is beginning of move east of Florida, with mid- upper level ridging covering the western Gulf. A line of showers and thunderstorms are seen along the Florida Panhandle from 29N-30N between 85W-88W. There are also dissipating showers seen 50 nm within the central coast of Louisiana. The trough along the Yucatan Peninsula is analyzed from 22N89W to 18N92W. Moderate to fresh southwesterly winds are seen in the north- central basin, with moderate to fresh southeasterly winds in the western Gulf. Gentle winds are in the eastern basin. A diurnal trough forming over the Yucatan Peninsula will produce fresh to strong winds each night as it moves NW over the SW Gulf of Mexico. Otherwise, a high pressure ridge will slowly move N from the central Gulf to the northern Gulf by Sunday, then persist there 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. An upper level trough extends to Puerto Rico and the Leeward Islands with a mid- upper level 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. Most of the activity in the Caribbean is associated with the tropical wave in addition to thunderstorms adjacent to the monsoon trough moving off the coasts of Panama and Costa Rica, S of 10N between 76W- 82W. There are also isolated showers approaching Puerto Rico. Fresh to strong winds continue across the central Caribbean. Moderate to fresh 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 until around dawn today, then again Friday night and Saturday night. Strong winds are expected to pulse over the Gulf of Honduras each night through Sunday night. A tropical wave near 65W will produce scattered thunderstorms with gusty winds as it moves W across the central and western Caribbean through Saturday. Elsewhere, generally moderate to fresh trades will prevail through the weekend and into early next week. ATLANTIC OCEAN... Scattered showers and isolated thunderstorms continue across the western Atlantic from 28N-30N between 67W- 75W. 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 28N54W and a 1022 mb high near 27N33W dominating the area. Strong winds will pulse N of Hispaniola until around dawn today and then again tonight. Fresh to strong winds will affect the northern waters through Friday ahead of a cold front that will move off the U.S. East Coast Friday night. A high pressure ridge will dominate much of the region through Saturday, then weaken Sunday into Monday as the cold front continues moving E across the western Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ AKR