000 AXNT20 KNHC 272338 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Fri Oct 27 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 2350 UTC. ...SPECIAL FEATURES... Tropical Storm Tammy: Tropical Storm Tammy is centered near 32.5N 61.4W at 27/2100 UTC or 170 nm E of Bermuda, moving NW at 3 kt. Estimated minimum central pressure is 988 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are 25 ft. Scattered moderate convection is from 32N to 35N between 57W and 61W. A turn to the north is expected tonight, followed by a turn to the east over the next couple of days. On the forecast track, Tammy will begin to move away from Bermuda Saturday morning. Gradual weakening is forecast during the next couple of days. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at 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. Western Atlantic Rough Seas: High pressure across the middle Atlantic coastal states is combining with a low level trough than extends from S of Tammy to the NE Caribbean to produce a large area of fresh to locally strong winds and very high seas between Tammy and the Bahamas. A large area of 12 ft to 15 ft seas is just northeast of the Bahamas and the Turks and Caicos Islands. These associated high seas between Tammy and the Bahamas will slowly begin to subside Sat through Sun. Mariners should either avoid this region or use extreme caution in this area, depending on your vessel type and cargo. Hazardous surf and rip currents are also anticipated along the coast of central Florida, the Bahamas, Greater Antilles and the northern Leeward Islands. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at the website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the Offshore Waters Forecast at https://www.nhc.noaa.gov/marine/offshores.php for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the Atlantic through the coast of Senegal near 14N17W and continues to 11N20W. The ITCZ extends from 11N20W to 05N53W along the coast of French Guiana. Scattered moderate to isolated strong convection is observed from 04N-12N bewteen 25W-50W. The eastern North Pacific monsoon trough extends from Central America along the coast of Nicaragua at 11N84W to 12N77W. Scattered moderate and isolated strong convection is noted from 10N-14N between 76W-82W. ...GULF OF MEXICO... A strong 10127 mb high pressure is centered over the Carolinas with a ridge extending west-southwest just north of the Gulf of Mexico. E winds are moderate to fresh with seas 5-7 ft over the central and eastern Gulf and gentle to moderate winds and 3-5 ft seas elsewhere. No deep convection is occuring over the Gulf this afternoon. For the forecast, high pressure centered across the middle Atlantic coastal states will continue to support moderate to fresh winds, strong in the eastern Gulf through early Sun. Mainly gentle NE winds are expected by Mon as the pressure gradient weakens and high pressure settles over the region. The next cold front is forecast to reach the NW Gulf on Mon. This front will bring gale force winds and quickly building seas over the western Gulf beginning on Mon night. ...CARIBBEAN SEA... High pressure over the SE United States along with lower pressure with the eastern North Pacific's monsoon trough is forcing fresh to strong NE winds over the NW Caribbean as well as the Windward Passage this afternoon. Elsewhere, winds are gentle to moderate. Seas are 6-8 ft in the NW Caribbean and the Windward Passage due to wind waves, as well as 6-8 ft in the Mona and Anegada Passages due to NNE swell. Seas elsewhere over the Caribbean are 3-5 ft. A sharp upper-level trough extends over the Greater Antilles and is inducing a surface trough in the eastern Caribbean from 10N-19N along 66W. While winds are generally weak with this trough, scattered moderate convection is occurring from 10N-20N between 60W-71W. For the forecast, strong high pressure centered over the middle Atlantic U.S. coast is combining with elongated low pressure extending from the W central Atlantic across the NE Caribbean will support fresh to strong NE to E winds in the NW and north- central Caribbean, including the Windward Passage through Sun. Gentle winds are expected elsewhere. ...ATLANTIC OCEAN... Please read the Special Features section above for more information on Tropical Storm Tammy east of Bermuda, and rough seas across the SW North Atlantic. The remainder of the tropical Atlantic is dominated by a subtropical ridge along 30N. The pressure gradient between the ridge and the ITCZ to the south is forcing generally moderate to fresh NE to E tradewinds over most of the Atlantic east of 60W. A trough and a dissipating stationary front extends from near the northern Leeward Island to just southeast of Tammy. Scattered moderate convection is occurring within 60 NM of the trough/front axis. Near the trough/front axis, the winds are gentle or weaker. However, large N to NE swell are occurring west of 55W, outside of the strong NE winds described in the Special Features. For the forecast W of 55W, Tammy has redeveloped into a Tropical Storm near 32.2W 61.1W at 1500 UTC, moving NW at 3 kt. Estimated central pressure is 988 mb. Maximum sustained winds are 55 kt gusting to 65 kt. High pressure across the middle Atlantic coastal states is combining with a low level trough than extends from S of Tammy to the NE Caribbean to produce a large area of fresh to locally strong winds and very high seas between Tammy and the Bahamas. These associated high seas between Tammy and the Bahamas will slowly begin to subside Sat through Sun. Tammy is expected to meander and remain N of the area waters through Sat, then move eastward and brush the far NE waters Sat night, then gradually weaken E of 55W early next week. Elongated low pressure will develop across the SE Bahamas Sun and gradually drift W through Tue. $$ Ramos