000 AXNT20 KNHC 151828 AAA TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Nov 15 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. ...updated to include information on the potential for TC genesis in the SW Caribbean... Based on 1200 UTC surface analysis and satellite imagery through 1740 UTC. ...SPECIAL FEATURES... ...Gulf of Mexico Gale-Force Wind Warning... A 1009 mb low pressure center is in the north central Gulf of Mexico. This low pressure center has been moving slowly toward the northeast during the last few days. A stationary front connects to the low pressure center, from the southern parts of Florida. A cold front connects to the low pressure center from the Yucatan Peninsula of Mexico. Gale-force winds, and sea heights that range from 8 feet to 12 feet, are from 29N to 30N between 85W and 86W. Elsewhere: from 27N to 30N between 82W and 91W, expect E winds from 20 knots to 30 knots, and sea heights from 8 feet to 12 feet. Expect NW to N winds from 20 knots to 25 knots, and sea heights to range from 9 feet to 11 feet, from 18N to 20N between 94W and 96W, including within 60 nm of the coast of Veracruz in Mexico. Elsewhere: from 19N to 23N between 93W and 97W, moderate or slower winds and sea heights from 8 feet to 10 feet in N to NE swell. Please, read the High Seas Forecast, MIAHSFAT2, at the following website, www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for more details on the gales. ...Offshore Florida and N of Bahamas Gale Warning... A complex low pressure system is expected to develop along a frontal boundary off the southeast coast of Florida Thu morning. A tight pressure gradient between strong high pressure to the NE and the broad area of low pressure center will support strong to near-gale force winds N of 27N and E of 70W beginning Thu. Gale force ENE winds are expected in the northern semicircle of the low, offshore central Florida and north of the Bahamas Thu afternoon and Thu night, supporting seas of 12-16 ft. ...Southwestern Caribbean Sea... The monsoon trough is along 08N/09N, from 75W in Colombia, beyond Panama and Costa Rica, and into the Pacific Ocean. A NW-to-SE oriented surface trough extends from the Yucatan Channel to 12N82W. Precipitation: widely scattered moderate to isolated strong is from 13N southward from 73W westward. Isolated moderate to locally strong is elsewhere from 70W westward. The environmental conditions appear to be marginally conducive for development of this system, during the next couple of days. It is possible that a tropical depression may form by this weekend. The system is forecast to move northeastward, through the western and central parts of the Caribbean Sea. An Air Force Reserve reconnaissance mission is scheduled to investigate the system tomorrow. This system is expected to produce heavy rains that may result in flash flooding and mudslides in parts of the Caribbean Sea coast of Central America and the Greater Antilles, through this weekend. Anyone who has interests in Jamaica, Cuba, Haiti, the Dominican Republic, the southeastern Bahamas, and the Turks and Caicos Islands, should continue to monitor the progress of this system. The chance of formation into a tropical cyclone during the next 48 hours is medium. Please, refer to the following website, www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2, for details. ...Sea Heights of 12 Feet or Higher... Sea heights of 12 feet or higher will start tonight, from 29N northward between 50W and 65W. Everything will spread eastward and southward during the next few days. The coverage of the 12 foot sea heights by Friday will be from 23N northward between 30W and 55W during the weekend. The peak seas from 15 feet to 16 feet, will occur between Thursday and Friday, from 30N northward. ...MONSOON TROUGH/ITCZ... The monsoon trough remains inland, in Guinea and in Senegal. A surface trough is in the coastal plains/the coastal waters of Africa from Senegal northward. The ITCZ is along 05N11W 06N15W 04N30W 02N43W. Broad upper level cyclonic wind flow covers the areas that are from 20N southward between 30W and 50W. Upper level anticyclonic wind flow is mixed with the cyclonic wind flow, from 13N to 23N from 50W eastward. Precipitation: widely scattered moderate to isolated strong is from the ITCZ to 10N between 32W and 47W. The SW part of an upper level Atlantic Ocean NE-to-SW oriented trough reaches the NE parts of South America, from French Guiana to NE Venezuela. Precipitation: isolated moderate to locally strong is from 06N to 13N between 53W and 64W. ...GULF OF MEXICO... Please, refer to the SPECIAL FEATURES section, for details about the gale-force winds forecast that is related to the 1009 mb low pressure center. A stationary front extends from 26N82W to low pres near 28N88.5W with cold front from the low to the Yucatan Peninsula. The low will continue to move ENE through the week, gradually dragging the fronts across the Gulf waters. Near-gale winds and rough seas will continue through Thu across the northern semicircle of the low. Marine conditions are expected to improve by the end of the week, with high pressure building across the basin this upcoming weekend. ...CARIBBEAN SEA... Please, refer to the SPECIAL FEATURES section, for details about the potential for heavy rain in the Caribbean Sea. Fresh to strong easterly winds, and rough seas, are in the central one-third of the area. Moderate seas cover much of the rest of the Caribbean Sea, except for the slight seas that are within 60 nm to 120 nm from land. Fresh to moderate NE winds are in the eastern one-third of the area. Moderate or slower winds are in the rest of the area. The monsoon trough is along 08N/09N, from 75W in Colombia, beyond Panama and Costa Rica, and into the Pacific Ocean. A NW-to-SE oriented surface trough extends from the Yucatan Channel to 12N82W. Precipitation: widely scattered moderate to isolated strong is from 13N southward from 73W westward. Isolated moderate to locally strong is elsewhere from 70W westward. The 24-hour precipitation totals in inches, for the period that ended at 15/1200 UTC, are: 0.38 in Trinidad, and 0.31 in Bermuda, 0.22 in Tegucigalpa in Honduras, and 0.18 in Curacao, according to the Pan American Temperature and Precipitation Tables, MIATPTPAN. Comparatively drier air in subsidence is from 70W eastward. Fresh to strong winds will prevail across the central Caribbean through late Wed. A broad area of low pressure is expected to form over the southwestern Caribbean in the next few days. Environmental conditions appear favorable for additional development of this system, and a tropical depression is likely to form toward the end of this week while the system begins moving northeastward across the western and central portions of the Caribbean Sea. Regardless of development, this system has the potential to produce heavy rains over portions of the Caribbean coast of Central America and the Greater Antilles through the end of this week. There is a high chance of tropical cyclone development in the next 7 days. ...ATLANTIC OCEAN... Please, refer to the SPECIAL FEATURES section, for details about the Offshore Florida and N of Bahamas Gale-Force Wind Warning. Two cold fronts extend southwestward, from the north central Atlantic Ocean, to the Bahamas, and to South Florida. Precipitation: isolated moderate to locally strong is from 20N northward from 30W westward. Broad surface anticyclonic wind flow is from 20N northward from the cold fronts eastward, with a surface ridge. Comparatively drier air in subsidence is in the Atlantic Ocean and in the Caribbean Sea, within 270 nm on either side of 22N40W 17N50W 15N58W 15N70W. Fresh to moderate winds, and moderate seas, cover the rest of the Atlantic Ocean. A frontal boundary extends from 31N49W to the central Bahamas to S Florida. Fresh to strong NE-E winds prevail N of the front with seas to 10 ft. High pressure will build in the wake of the front N of the area today. This will support an area of strong to near-gale winds over the waters N of 25N and W of 70W beginning tonight. A broad area of low pressure may develop over the waters W of 75W the second half of the week, with the strong to near-gale force winds shifting to the waters N of 27N and W of 70W toward the end of the week. Gale force winds are possible N of 27N Thu afternoon and Thu night, lifting N of 31N Fri afternoon. The low will drag a frontal boundary across the waters in its wake through the upcoming weekend. $$ mt/al