000 AXNT20 KNHC 182328 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Nov 19 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... Heavy Rainfall and Flooding for Hispaniola: A trough extending from 26N67W southwestward to Haiti and to well into the Caribbean Sea to near 13N77W will linger into early next week. Numerous large clusters of strong convection are over most of the Dominican Republic and adjacent waters. Scattered moderate convection is over the eastern and central sections of Haiti. Heavy rainfall from this convection is likely to produce flash flooding, along with mudslides in hilly terrain. Please consult products from your local weather office. Significant North Swell in the Central Atlantic: Large north swell generated by an earlier storm at the north Atlantic has reached as far south as 18N in the central Atlantic between about 28W-53W. Seas of 10-15 ft are noted north of 18N between 35W and 55W. This swell will gradually decay through Sun, with seas subsiding to below 12 ft. Please read the latest High Seas Forecast issued by the National Hurricane Center at the website www.nhc.noaa.gov/text/MIAHSFAT2.shtml latest Offshore Water Forecast west of 55W at www.nhc.noaa.gov/marine/offshores.php for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic along the Guinea- Bissau coast and extends southwestward to 10N19W, where latest scatterometer data indicates that it transitions to the ITCZ to 07N30W to 06N39W and 05N48W. Scattered moderate convection is seen within 60 nm south of the trough between 21W-29W, and within 60 nm north of the ITCZ between 31W-25W. Similar activity is north of the ITCZ from 07N to 09N between 41W-45W. Scattered moderate to isolated strong convection is along and inland the coast of Africa between 05W-10W. ...GULF OF MEXICO... A weak cold front extends from near Mobile, Alabama southwestward to 26N93W, where it transitions to a stationary front that continues to inland southern Texas near Brownsville. However, no significant convection is associated with this front. Elsewhere, high pressure of 1021 mb centered over eastern Mexico near 22.5N98W is building eastward. The gradient in place is allowing for a gentle to moderate northerly flow to exist across the basin. Seas are 2-4 ft throughout. For the forecast, high pressure is building across the Gulf waters producing light to gentle northwest to north winds over the western half of the Gulf, and mainly moderate N winds over the eastern half of the Gulf, including the Yucatan Channel. These winds will veer to the east and southeast on Sun. Southerly return flow will increase over the western Gulf Sun night ahead of the next cold front which will move off the Texas coast Mon night into Tue. Gale conditions are likely in the wake of the front over the west-central and southwest sections of the Gulf Tue through Wed. Seas are forecast to build to 14 to 16 ft over the SW Gulf by Tue night into Wed morning. ...CARIBBEAN SEA... Please refer to the SPECIAL FEATURES section for details about the heavy rain and flooding potential for Hispaniola. Weak low pressure of 1009 mb is centered near 19N84W and is producing no convection. A trough extends from northeast and east of the southeastern Bahamas southwestward to near 13N77W. The eastern end of the Pacific monsoon trough axis protrudes into the far southwestern Caribbean. Scattered moderate to isolated strong convection is confined to south of 13N between 75W-80W. Latest ASCAT data passes reveals fresh west to northwest winds south of 19N and west of 83W, while mostly gentle west to northwest winds are elsewhere west of 79W. Fresh southeast winds are in the eastern Caribbean. Seas are 5-7 ft, except for seas of 4-6 ft north of 18N west of 80W and 2-4 ft from 18N to 20N between 76W-80W. For the forecast, the pressure gradient between a ridge across the Yucatan Peninsula and northern Central America and low pressure over the northwestern Caribbean supports and area of fresh to strong west to northwest winds from about 16N to 20N and west of 83W. These winds are expected to change little through tonight. A trailing surface trough will remain over the central Caribbean into Tue. Weak low pressure may develop along the trough axis. Fresh to locally strong northerly winds are expected west of the trough and mainly offshore Nicaragua through Sun. ...ATLANTIC OCEAN... Please refer to the SPECIAL FEATURES section for details about large north swell in the central Atlantic. A trough extends from near 26N67W southwestward to Haiti. Numerous moderate to isolated strong convection is east of the trough to near 57W as well as north of the trough. Low Low pressure of 1007 mb is analyzed near 31N76W. A frontal trough extends from this low to the central Bahamas and to west- central Cuba. Scattered moderate convection moving quickly eastward is north of 26N between 69W and the trough and low. Scattered showers are west of the low and trough to 79W and north of 28N. ASCAT data passes from this afternoon show fresh to strong northwest to north winds north of 27N and west of the frontal trough. In the central Atlantic, a stationary front extends from near 31N29W southwestward to 25N40W and to 24N50W. Fresh to strong northeast winds are north of this frontal boundary along with seas of 10-15 ft in north swell as described above under the Special Features section. Moderate to fresh trades are southeast and south of the stationary frontal boundary along with seas of 5-7 ft. Lower seas of 2-4 ft are southwest of the Bahamas. For the forecast W of 55W, the aforementioned low of 1007 mb will lift north of the area in a few hours, with fresh to strong northwest to north winds continuing west of the frontal trough, and fresh to strong southerly winds ahead of the trough. The remnants of Potential Tropical Cyclone Twenty-Two continue to quickly move northeast. They are forecast to merge with the frontal trough on Sun. $$ Aguirre