000 AXNT20 KNHC 180844 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sun Jun 18 2023 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 0800 UTC. ...SPECIAL FEATURES... Gale Warning Eastern Tropical Atlantic Low (AL92): A tropical wave located several hundred miles SW of the Cabo Verde Islands with axis near 31W and with a 1010 mb low near 09.5N30.5W. The wave axis extends from 04N to 13N, and is moving W at around 15 kt. Scattered moderate convection is observed from 06N to 12N between 30W and 36W. This activity is gradually becoming better organized and environmental conditions appear conducive for additional development. A tropical depression is likely to form over the next couple of days. This system is expected to move westward at 15-20 kt across the eastern and central tropical Atlantic through the middle part of this week, with associated winds and seas spreading W of 35W by this evening. Winds are forecast to reach 35 kt or greater by late Mon night and a gale warning has been issued. There is a high (70%) chance of tropical cyclone development through the next 48 hours, and a high (90%) chance of development through the next seven days. Please refer to the latest Tropical Weather Outlook at www.hurricanes.gov, for more details. ...TROPICAL WAVES... Please refer to the Special Features section for information on the tropical wave (with AL92) in the eastern Atlantic. A central Atlantic tropical wave extends along 45W from 01N to 10N, moving W at 15-20 kt. Only isolated showers and thunderstorms are observed in the vicinity of the tropical wave. A tropical wave is mainly inland S of Trinidad and Tobago along 61W/62W across far eastern Venezuela and into northern Brazil from 01N to 10N, moving W at around 15 kt. Associated convection is confined to inland locations. A SW Caribbean Sea tropical wave extends along 82W/83W from 14N southward into the tropical eastern Pacific Ocean, moving W at around 20 kt. Scattered moderate convection is observed from 11N to 15N between 82W and 84W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 17N16W to 05N46W. No ITCZ is currently present. In addition to the convection associated with the tropical waves, scattered moderate to strong convection is observed from 05N to 14N east of 23W, likely associated with the next tropical wave. GULF OF MEXICO... Weak surface ridging prevails across the majority of the basin, supporting gentle to moderate S-SW winds across the Gulf. A surface trough extends just NW and offshore the Yucatan Peninsula, with moderate to fresh winds on either side of it. Seas are 3-5 ft W of 91W, and 2-4 ft E of 91W, except 1-3 ft in the SE Gulf through the Straits of Florida. In the NE Gulf, middle to upper level diffluence is supporting thunderstorms in the coastal waters off the Florida Peninsula. Smoke due to agricultural fires over Mexico may be reducing visibilities in coastal waters from the Yucatan Peninsula westward. For the forecast, high pressure extending from the Atlantic through the Straits of Florida and to the upper Texas coast will generally persist through the next several days. Fresh winds will pulse north of the Yucatan peninsula each night through the forecast period as a diurnal trough develops and moves offshore. Elsewhere, gentle to moderate winds will prevail, except locally fresh in the NW and W central Gulf today through Thu night. A weak front may sink into the far northern Gulf by mid-week. Smoke from agricultural fires in Mexico will produce hazy skies over the central and western Gulf for at least the next day or two. CARIBBEAN SEA... Please see the Tropical Waves section for information on a tropical wave in the SW Caribbean and another tropical wave over eastern Venezuela. The gradient between subtropical high pressure and lower pressure over the SW Caribbean is supporting fresh to strong easterly trade winds in the central Caribbean and Gulf of Honduras as noted by earlier ASCAT scatterometer data. Trade winds are gentle to moderate elsewhere across the basin. Seas are 8-10 ft in the central and SW Caribbean per a recent altimeter pass, and 4-7 ft across the remainder of the basin. Smoke due to agricultural fires over portions of Central America may be reducing visibilities in the NW Caribbean to the Yucatan Peninsula. For the forecast, the pressure gradient between the Bermuda High and the Colombian Low will support fresh to strong E trades from the central Caribbean to Nicaragua through this morning, then again across the central Caribbean tonight through early Wed. Fresh to strong E winds are expected in the Gulf of Honduras before sunrise today, then moderate to fresh through at least Thu. Scattered to numerous thunderstorms are expected across SW portions to the west of 76W through tonight. A strong tropical wave, and possible tropical cyclone, will move across 55W and into the Tropical Atlantic waters Thu and Thu night. ATLANTIC OCEAN... Please refer to the Special Features section for information on a gale warning and associated area of low pressure (AL92) in the eastern Atlantic which has a high tropical cyclone development potential. High pressure of 1025 mb centered near 32N47W extends a ridge WSW to the central Bahamas and ESE to the Canary Islands. This is supporting mainly moderate to locally fresh winds across the subtropical Atlantic waters, except gentle to moderate right under the ridge axis. Seas are 3-5 ft W of 70W, 3-4 ft N of 24N between 35W and 55W, and 4-7 ft elsewhere. In the far western Atlantic, a mid to upper level trough is generating heavy showers and thunderstorms N of 24N and W of 64W, including the northern and central Bahamas. Winds and seas may be higher in and near any convection. For the forecast W of 55W, Bermuda high pressure extends a ridge N of the area which will continue to dominate through mid-week. A weak cold front or trough may shift offshore N Florida and stall early in the week before dissipating. Mainly gentle to moderate anticyclonic winds will prevail the next several days, locally fresh offshore N Hispaniola and offshore N Florida. A strong tropical wave, and possible tropical cyclone, will move across 55W and into the Tropical Atlantic waters Thu. $$ Lewitsky