000 AXNT20 KNHC 141806 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Dec 14 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 1800 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning: A 1006 mb low is located near 26N43W. Near gale to gale- force northeast to east winds along with seas of 15 to 18 ft are occurring northwest of the low from 26N to 30N between 40W-46W. Near gale force to gale force winds are also likely on the east side of the low from 24N to 26N between 39W and 40W. Satellite imagery shows a band of scattered moderate convection north of 20N between 37W and 41W. This activity is shifting north- northeastward. This system will slide off to the east- northeast through this evening. As it does, the tight pressure gradient producing the gales will weaken just enough to allow for the gale-force winds to drop to just below gale criteria. Seas will gradually subside through Fri within the area of the low pressure system. Atlantic Significant North Swell: Large north swell due to the gale force low continues to sustain 12 to 15 ft seas from 23N to 31N between 39W and 51W. This swell will subside by this evening west of 45W. Seas east of 45W and north of 25N will remain elevated through tomorrow afternoon due to ongoing near gale force winds associated with the low pressure system mentioned above. Western Atlantic and Florida Offshore Waters Gale Warning and Significant Swell Event: A frontal boundary extends over the northern Bahamas to the Florida Straits. A recent ASCAT pass shows a large swath of near gale- force northeast winds north of the boundary and west of 68W. Gale force winds are likely occurring over waters between the Bahamas and Florida from 26N to 27N. Seas within these areas of winds are 9 to 13 ft. The prevailing tight pressure gradient between strong high pressure over the eastern U.S. and lower pressures in the Gulf of Mexico and NW Caribbean will support near gale force to gale force winds offshore Florida through the weekend. Seas will build to 15 ft between Florida and the Bahamas and 15 to 17 ft between 26N and 29N behind the front by Fri. Seas of 12 to 14 ft will spread southward between 60W and the north facing coasts of the Bahamas, reaching 22N by Sat morning. Seas will gradually subside through the weekend. Gulf of Mexico Gale Warning: Strong high pressure building over the eastern U.S. is tightening the pressure gradient across the Gulf of Mexico, supporting frequent gusts to gale- force offshore of the Florida Panhandle. Winds will increase to gale force over the NE Gulf tonight through Fri. Low pressure will form in the SW Gulf by Fri night then move NE and into Florida Sat night through Sun. This will cause additional gales in the NE Gulf. A cold front will trail from the low, exiting the Gulf early on Sun. Expect widespread showers and thunderstorms over most of the central and eastern Gulf through early Sun. Seas with these winds are forecast to be 10-15 ft. Winds diminish and seas subside by Sun morning. For more details on the Significant Swell and Gale Warnings, please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml. ...MONSOON TROUGH/ITCZ... The monsoon trough remains mainly inland over Africa. The ITCZ begins near 07N12W, continues to 06N30W to 03N47W. No significant convection is noted at this time. ...GULF OF MEXICO... Please read the Special Features section for details on a frequent gust Gale Warning in the NE Gulf and a forming gale force low pressure system occurring this weekend. A stationary front related to the boundary in the western Atlantic Gale force winds Special Feature, enters the Gulf of Mexico through the Florida Straits. Recent data from satellite imagery and ASCAT observations suggest the front extends westward into the Gulf to near 22N93W. A large swath of strong to near gale force E winds is noted behind the boundary with rough seas of 8 to 13 ft. West of 92W, fresh to strong E winds with 6 to 10 ft seas are noted. A surface trough is depicted in the SW Gulf. Fresh NE winds shifting NW south of 22N surround the feature. Broken to overcast multilayered clouds along with scattered to numerous showers and areas of moderate rain are over the basin north of 23N. For the forecast, strong high pressure building across the eastern United States will continue to support strong to near gale force winds over the central and eastern Gulf with fresh winds over the western Gulf. After the passing of the gale force low pressure system, fresh to strong north winds will filter into the western Gulf Sat and Sat night. High pressure will then settle in over the area through early next week allowing for marine conditions to improve. ...CARIBBEAN SEA... A recent scatterometer pass shows fresh to strong NE winds over most of the central basin, with the strongest winds noted offshore Colombia, within the Windward Passage, south of Hispaniola, and in the NW Caribbean north of 20N. Moderate to fresh winds are noted elsewhere. Seas are up to 12 ft offshore Colombia, 8 to 10 across the central basin and 6 to 8 elsewhere. For the forecast, strong high pressure N of the region will support fresh to strong trade winds across the central and eastern Caribbean today, before gradually diminishing. Fresh to strong northeast winds in the Windward Passage will diminish Fri night. A cold front will move through the Yucatan Channel and into the NW Caribbean Sat night into Sun. ...ATLANTIC OCEAN... Please read the SPECIAL FEATURES section for details about the the ongoing gale warnings and the Significant North Swell. A cold front extends from 31N65W, transitioning to stationary near the northern Bahamas. Aside from those conditions described above under Special Features, an area of fresh to strong winds is noted in recent scatterometer imagery south of 24N and west of 55W to the Greater Antilles, where seas are 8 to 10 ft. Elsewhere, moderate to fresh winds along with moderate seas are throughout the rest of the basin. For the forecast, by Sun winds are expected to increase again as low pressure is forecast to cross Florida from the Gulf of Mexico Sat night and move into Atlantic waters. A large area of gale force winds is possible east of the low. Widespread showers and thunderstorms are expected over most of the western half of the area through the weekend. $$ Mora