000 AXNT20 KNHC 201800 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Nov 20 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 1200 UTC surface analysis and satellite imagery through 1740 UTC. ...SPECIAL FEATURES... ...Western Atlantic Ocean and Central Atlantic Ocean Gale-Force Wind Warning... A cold front extends from a 1006 mb 31N62W low pressure center, to just to the north of the Dominican Republic, and curving to the coast of Cuba near 22N78W. Expect gale- force SW winds, and sea heights that range from 10 feet to 12 feet, from 29N to 30N between 60W and 61W. Elsewhere: from 23N to 31N between 58W and 75W SW to W winds from 20 knots to 30 knots, and sea heights ranging from 10 feet to 12 feet. Expect: winds 20 knots or less, and sea heights ranging from 8 feet to 10 feet in SW to W swell, in the remainder of the area that is from 22N to 31N between 54W and 73W. Precipitation: isolated moderate to locally strong from 20N northward between 50W and the cold front. The 36N40W 1026 mb high pressure center is forecast to weaken. The surface pressure gradient will relax enough. The wind speeds will be less than gale-force, later today. Building high pressure from off the Mid-Atlantic U.S.A. that is to the NW of the cold front will lead to rapidly increasing NW and N winds behind the cold front later today. Northerly gale-force winds will develop by this evening from 28N northward from 63W eastward. The gale-force winds will spread eastward, behind the cold front as the cold front crosses 55W late on Tuesday. The wind speeds should slow down gradually to less than gale-force on Wednesday morning. An expanding area of rough seas that will range from 15 feet to 20 feet will accompany the gale-force winds. Sea heights 12 feet or higher should end up covering the Atlantic Ocean by Wednesday morning from 22N northward between 48W and 65W. It is possible that a low pressure center may form along this cold front near 30N50W by mid-week. It is possible that the low pressure center may separate from the cold front. The faster wind speeds will continue in parts of the Central Atlantic late this week. ...Gale-force Winds in the Gulf of Mexico... A cold front will move off the Texas coast tonight. The front will reach from near Mobile Bay to just S of Veracruz, in Mexico, on Tuesday. NW to N winds will increase rapidly behind the cold front. Gale-force winds will develop by Tuesday afternoon offshore Tampico in Mexico. These gale- force winds will spread southward, and they will impact the waters that are offshore Veracruz in Mexico, from Tuesday evening through at least midday on Wednesday. The sea heights in the west central Gulf, and in the SW Gulf will range from 12 feet to 16 feet. The front will be well to the east of the area by Wednesday night, and the wind speeds and the sea heights will decrease. Please, read the latest High Seas Forecast, that is issued by the National Hurricane Center, at the website - www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the latest Offshore Waters Forecast to the west of 55W, at www.nhc.noaa.gov/marine/offshores.php, for details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of southern Liberia, to 05N19W. The ITCZ continues from 05N19W, to 05N26W and 02N40W. Precipitation: widely scattered moderate to isolated strong is from 10N southward from 50W A surface trough curves from Senegal to 20N19W and 27N19W. Precipitation: broken to overcast multilayered clouds, and isolated moderate to locally strong, are to the south and to the east of the line 30N10W 30N20W 10N50W. ...GULF OF MEXICO... Please, read the SPECIAL FEATURES section, for details about the developing gale-force wind event. Fresh to strong SE and S winds are from 93W westward. Mostly moderate to some fresh SE winds are in the rest of the Gulf of Mexico. Slight seas are everywhere in the Gulf of Mexico at the moment. Fresh southerly return flow is expected over the western Gulf ahead of the next cold forecast to enter the NW Gulf tonight. The front will reach from south-central Louisiana to near Veracruz, Mexico by Tue morning, and from the Big Bend of Florida to the central Bay of Campeche by Wed morning. Gale force winds will develop over the west- central and SW Gulf Tue morning through Wed. Rough to very rough seas are expected over the SW Gulf by Tue through Wed. ...CARIBBEAN SEA... A 1008 mb low pressure center is near 14N73W, INVEST-AL99. A surface trough extends from the low pressure center to the Mona Passage. Earlier satellite wind data were indicating that the small but well-defined area of low pressure was producing winds that were ranging from 25 mph to 30 mph. Precipitation: scattered to numerous strong is from 14N to 18N between 66W and 70W. Widely scattered moderate to isolated strong is within 120 nm on either side of the low pressure center and the trough, and from 18N northward between 60W and 70W. Nearby dry air is forecast to prevent much additional development. The system is forecast to drift slowly westward during the next few days. A second 1008 mb low pressure center is near 14N78W. Broken multilayered clouds and possible isolated rainshowers are elsewhere to the east of the line from NE Nicaragua and SE Cuba. The monsoon trough extends from the INVEST-AL99, beyond Costa Rica, and into the Pacific Ocean. Precipitation: isolated moderate is from 12N southward from 75W westward. Moderate seas are from the Windward Passage eastward. Slight seas cover the rest of the Caribbean Sea. Fresh to moderate SE winds are to the east of the surface trough. Moderate to fresh winds surround the INVEST-AL99 low pressure center. Mostly gentle winds are in the remainder of the central one-third of the area. Moderate or slower winds are elsewhere. The 24-hour precipitation totals in inches, for the period that ended at 20/1200 UTC, are: 0.27 in Bermuda, and 0.11 in Curacao, according to the Pan American Temperature and Precipitation Tables, MIATPTPAN. Weak low pressure off the coast of Colombia in the south central Caribbean has increased shower and thunderstorm activity. Environmental dry air is still likely to prevent significant development of this system as it begins to drift slowly westward later this week. This system has a low chance of formation in the next 48 hours and 7 days. High pressure building toward the Greater Antilles Tue into Wed will lead to fresh to strong NE winds in the Windward Passage and just S of Hispaniola. Elsewhere, winds will be moderate or less into late week. ...ATLANTIC OCEAN... Please, refer to the SPECIAL FEATURES section, for details about the western Atlantic Ocean and central Atlantic Ocean Gale-force Wind Warning. A stationary front passes through 31N23W, to 24N30W 24N40W 31N47W. Precipitation: widely scattered moderate to isolated strong is within 120 nm on either side of the front from 25N northward. Isolated moderate is within 120 nm on either side of the rest of the front. Moderate to fresh winds cover the rest of the Atlantic Ocean from 30W westward. Moderate or slower winds are from 30W eastward. Moderate to rough seas cover the rest of the open waters of the Atlantic Ocean. Slight seas are from the Bahamas southward. A cold front that extends E of Bermuda to east of the Turks and Caicos Islands will slide E through mid-week, before moving E of the region. Southerly gales ahead of the front N of 29N between 60W and 65W will diminish today. Behind the front, N winds will reach gale force by this evening into tonight N of 29N between 60W and 65W, then track eastward through Tue night to 55W. Very rough to high seas will accompany these gales, with northerly swell leading to seas of over 12 ft for areas N of 20N and E of 65W by Wed. Looking ahead, increasing southerly flow is likely mid-week offshore Florida in advance of the next cold front. $$ mt/ar