000 AXNT20 KNHC 220603 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sun Oct 22 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 0000 UTC surface analysis and satellite imagery through 0605 UTC. ...SPECIAL FEATURES... The center of Hurricane Tammy, at 22/0600 UTC, is near 17.9N 62.1W. This position also is about 24 nm/45 km to the NW of Barbuda, and about 54 nm/100 km to the E of St. Martin. Tammy is moving NNW, or 330 degrees, 09 knots. The estimated minimum central pressure is 992 mb. The maximum sustained wind speeds are 75 knots with gusts to 90 knots. The radius of hurricane- force winds is: within 20 nm of the center in the NE quadrant; within 10 nm of the center in the SE quadrant; within 10 nm of the center in the SW quadrant; and within 20 nm of the center in the NW quadrant. The radius tropical-storm force winds is: within 110 nm of the center in the NE quadrant; within 110 nm of the center in the SE quadrant; within 30 nm of the center in the SW quadrant; and within 70 nm of the center in the NW quadrant. The sea heights that are 12 feet or greater are: within 180 nm of the center in the NE quadrant; within 150 nm of the center in the SE quadrant; within 90 nm of the center in the SW quadrant; and within 150 nm of the center in the NW quadrant. The maximum sea heights are 26 feet. Precipitation: scattered strong is around Hurricane Tammy, from 13N to 20N between 59W and 63W. Please, consult bulletins and forecasts from your local weather office. Read the latest HIGH SEAS FORECAST, that is issued by the National Hurricane Center, at the website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the latest Tammy NHC Forecast/Advisory and Public Advisory, at www.hurricanes.gov, for more details. ...EASTERN ATLANTIC OCEAN STORM-FORCE WINDS... The METEO-FRANCE forecast consists of storm-force winds for the marine areas AGADIR and MADEIRA. Please, refer to the website, https://wwmiws.wmo.int/index.php/affiche/2, for details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of SW Senegal, to 09N25W. The ITCZ continues from 09N25W, to 06N30W, 06N40W, and 06N46W. A surface trough curves along 14N48W 08N50W, to 01N52W in Brazil. Precipitation: scattered moderate to isolated strong is from 05N to 17N between 26W and 50W. Isolated moderate to locally strong is in the remainder of the area that is from 23N southward from 60W eastward. ...GULF OF MEXICO... Comparatively drier air in subsidence is apparent in water vapor imagery, within 360 nm to 600 nm to the north of the line that passes through central Cuba, to the Gulf of Honduras. Upper level anticyclonic wind flow spans the Gulf of Mexico. A cold front is along 31N70W in the Atlantic Ocean, to Florida near 28N, to 28N87W, in the NE corner of the Gulf of Mexico. Precipitation: rainshowers are possible from 26N northward from 88W eastward. A surface ridge passes through the Straits of Florida, to a 1014 mb high pressure center that is near 26N92W. Slight seas cover most of the area. An exception is for some moderate seas in the NE corner of the area, from the cold front northward. Mostly moderate to some fresh winds are in the western half of the area. Moderate or slower wind speeds, are in the eastern half of the area. A cold front has stalled now from the Florida Big Bend to offshore Louisiana. This front will remain stationary overnight, then weaken and dissipate Sun. Another cold front skirt the far NE Gulf Sun night into Mon. High pressure will build in thereafter, leading to moderate to fresh SE winds by Mon. Mon night into Tue, winds will increase further, with areas of strong winds developing and persisting through at least the middle of next week. ...CARIBBEAN SEA... Please, read the SPECIAL FEATURES section, for details about Hurricane Tammy. A surface trough passes through 24N70W in the SE Bahamas, through the Windward Channel, to NW Jamaica, to 16N83W. The monsoon trough is along 09N/10N from 74W in Colombia, beyond Costa Rica, and into the Pacific Ocean. Precipitation: isolated moderate to locally strong is from Haiti westward. Moderate NE winds are on the northern side of the surface trough from 80W westward. Fresh northerly winds are from the surface trough southward from 80W westward. Moderate or slower wind speeds are elsewhere in the area. Precipitation: scattered strong is around Hurricane Tammy, from 13N to 20N between 59W and 63W. Isolated moderate to locally strong is elsewhere from 70W eastward. Broad upper level cyclonic wind flow is from 70W eastward. Broad surface lower pressure is in the SW corner of the Caribbean Sea. The precipitation has been increasing in coverage. The environmental conditions appear to be generally favorable for some more development of this system during the next day or two, before it moves inland, into Central America by Tuesday. The monsoon trough is along 09N/10N from 74W in Colombia, beyond Costa Rica, and into the Pacific Ocean. Precipitation: scattered to numerous strong is within 200 nm to the south of the monsoon trough between 81W and 86W. The 24-hour rainfall totals in inches, for the period that ended at 21/0000 UTC, according to the MIATPTPAN, are: 1.61 in Bermuda; 0.43 in Curacao; and 0.19 in Guadeloupe. Fresh SE winds have been within 420 nm of the center of Hurricane Tammy, in the NW quadrant. Strong or faster winds have been within 300 nm of Hurricane Tammy in the E semicircle. Some moderate seas are from Puerto Rico eastward. Slight seas cover the rest of the Caribbean Sea. Hurricane Tammy is near 17.8N 61.9W at 11 PM EDT, and is moving north-northwest at 9 kt. Maximum sustained winds are 75 kt with gusts to 90 kt, and the minimum central pressure is 992 mb. Tammy will move to 18.8N 62.5W Sun morning, 20.2N 63.4W Sun evening, and 21.5N 63.9W Mon morning. Hurricane Tammy will reach 22.6N 63.8W Mon evening, 23.1N 63.6W Tue morning, and 23.5N 63.0W Tue evening. Tammy will change little in intensity as it moves farther N of the Leeward Islands late Wed. A broad area of low pressure located over the southwestern Caribbean Sea continues to produce disorganized showers and thunderstorms. Some slow development of this system is possible before it moves inland over Central America by late Monday. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for details about Hurricane Tammy. A cold front is along 31N70W in the Atlantic Ocean, to Florida near 28N, to 28N87W, in the NE corner of the Gulf of Mexico. Precipitation: rainshowers are possible from 26N northward from 88W eastward. A surface trough passes through 24N70W in the SE Bahamas, through the Windward Channel, to NW Jamaica, to 16N83W. Moderate to rough seas are from the cold front northward from 30W westward. A surface trough is along 31N62W 27N68W, at the southern end of a cold front that is to the north of the area. Precipitation: isolated moderate to locally strong is from 20N northward between 57W and 70W. Moderate and fresh southerly winds are from 23N northward between 57W and 70w. Moderate to rough seas are from 62W westward, in general. The comparatively highest seas are from 23N67W 27N74W northward. Moderate to rough seas are from 17N northward between 50W and 62W, associated with Hurricane Tammy. A cold front passes through 31N12W, to the Canary Islands, to 26N20W, to 25N30W, to 31N41W. Precipitation: broken to overcast multilayered clouds, and isolated moderate, are from 23N northward from 42W eastward. Strong and faster winds are from the Canary Islands northward from 20W eastward. Fresh to strong winds are from the cold front northward between 20W and 30W. Moderate and fresh easterly winds are between 26W and 53W. Rough seas are from the cold front northward from 20W eastward. A surface trough passes through the coastal plains of Mauritania, near 20N16W, from 18.5N to 20N, between the coast of Africa and 37W. Precipitation: broken to overcast multilayered clouds, and isolated moderate, are within 60 nm on either side of the surface trough. Moderate seas are between the surface trough, and the cold front, that is about 350 nm to the north of it. Moderate seas, and moderate or slower wind speeds, are in the remainder of the Atlantic Ocean. A surface ridge extends from a 1028 mb high pressure center that is near 37N40W, through 31N45W, to 24N53W, 25N70W, toward the Straits of Florida. Hurricane Tammy is near 17.8N 61.9W at 11 PM EDT, and is moving north-northwest at 9 kt. Maximum sustained winds are 75 kt with gusts to 90 kt, and the minimum central pressure is 992 mb. Tammy will move to 18.8N 62.5W Sun morning, 20.2N 63.4W Sun evening, and 21.5N 63.9W Mon morning. Hurricane Tammy will reach 22.6N 63.8W Mon evening, 23.1N 63.6W Tue morning, and 23.5N 63.0W Tue evening. Tammy will change little in intensity as it moves farther N of the Leeward Islands late Wed. Farther W, a cold front has stalled from 31N70W to the northern Peninsula of Florida. This front will remain stationary while weakening through Sun. A second cold front will move off SE Florida Sun, overtake the stationary front Sun night, then reach a Bermuda to Fort Lauderdale, Florida, line, Mon. Looking ahead, high pressure building in the wake of the front combined with the impacts of Hurricane Tammy will bring an increase in winds and seas across the forecast area Tue into Wed night. $$ mt/sk