000 AXNT20 KNHC 121105 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Sep 12 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Major Hurricane Lee is centered near 24.0N 65.4W at 5 AM EDT, or about 575 miles S of Bermuda, moving west-northwest at 6 kt. Maximum sustained winds are 100 kt with gusts to 120 kt. Minimum central pressure is 948 mb. Lee continues to exhibit a ragged eye feature this morning. Numerous strong convection is noted within 90 nm NW and 45 nm SE semicircles of Lee. Scattered to numerous moderate to strong convection is elsewhere within 180 nm of the center. Seas in excess of 12 ft reach as far as 360 nm in the northern semicircle, 270 nm in the SE quadrant, and 300 nm in the SW quadrant with maximum seas of 42 ft. Lee is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Lee will move slowly NW through tonight then turn N Wed through Fri. On this forecast track, Lee is expected to pass near, but to the west, of Bermuda in a few days. Little change in strength is forecast during the next couple of days. Large swells generated by Lee is affecting the majority of the Atlantic waters from the Lesser Antilles, the British and U.S. Virgin Islands, Puerto Rico, Hispaniola, northward and westward to Bermuda, and the Bahamas and waters to 78W. These swells will likely cause very large and dangerous surf and life-threatening rip current conditions. These dangerous surf and rip currents have already begun to affect portions of the southeastern U.S. coast, and are expected to increase and spread northward along much of the U.S. East Coast during the next few days. Please consult products from your local weather office. Hurricane Margot is near 29.3N 39.5W at 5 AM EDT, or about 935 miles SW of the Azores, moving north at 11 kt. Maximum sustained winds are 75 kt with gusts to 90 kt. Minimum central pressure is 979 mb. Margot has also exhibited a small and ragged eye overnight. Numerous strong convection is noted within 90 nm across the SW semicircle of Margot. Bands of scattered moderate to isolated strong convection are elsewhere within 300 nm of the center. Seas in excess of 12 ft reach as far as 180 nm NE, 210 nm SE, 165 nm SW and 150 nm NW quadrants with maximum seas of 27 ft. Margot is moving toward the north, and this motion is expected to continue for the next several days. Slight strengthening is forecast during the next 48 hours. 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 NHC Forecast/Advisory and Public Advisory on Lee and Margot at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave (AL98) located over the far eastern tropical Atlantic between the Cabo Verde Islands and the west coast of Africa is producing disorganized showers and thunderstorms. Its axis is along 22W S of 18N. A 1009 mb mb surface low is analyzed near 12N22.5W. Environmental conditions appear conducive for gradual development of this system, and a tropical depression could form by the weekend while it moves westward to west- northwestward at 15 kt over the central tropical Atlantic. Currently, this system has a low chance of tropical cyclone formation through 48 hours, and a medium chance through 7 days. A weak 1012 mb area of low pressure (AL97) located several hundred miles west-southwest of the Cabo Verde Islands, near 12N32W, is producing disorganized shower and thunderstorm activity. This low has become stationary tonight and is expected to remain so for the next few days. Development of this system is unlikely before it merges with the tropical wave (AL98) incoming from the east during the next couple of days. As a result, there is a low chance of tropical cyclone formation during the next 7 days. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details on AL97 and AL98. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean through the coast of Senegal near 13.5N17W, then continues southwestward to a 1009 mb low pressure (AL97) near 12N22.5W, through 1012 low pressure near 12N32W to 12.5N36W. No ITCZ is currently present. Scattered moderate to strong convection is noted from 06N to 16.5N between the W coast of Africa and 38W, including within about 120 nm W of the weak area of low pressure (AL97). ...GULF OF MEXICO... A weak frontal trough recently stretching across the north central Gulf has shifted inland across SE Texas and southern Louisiana. A weak ridge extends from 1018 mb high pressure over the western Atlantic into the northeastern Gulf. This pattern is supporting only light to gentle winds and slight seas across the basin. A middle to upper level trough moving slowly across the western and north central Gulf of supporting scattered showers and thunderstorms across the NE Gulf north of 27N between 85W and 87.5W, as well as lingering scattered moderate convection from the Bay of Campeche to the waters offshore of the NW Yucatan Peninsula. For the forecast, a weak ridge will dominate the Gulf waters throughout the forecast period supporting mainly light to gentle winds. Moderate return flow will develop across the W and SW Gulf on Thu. Scattered thunderstorms can be expected across the western Yucatan and eastern Bay of Campeche each late afternoon and evening. ...CARIBBEAN SEA... Please read the Special Features section about large swell generated by Major Hurricane Lee impacting the northeast Caribbean islands. Scattered moderate to strong convection dots the Gulf of Honduras, and is also seen across the SW Caribbean south of 12N between NW Colombia and 82W. Fair weather is otherwise dominating the basin this morning. The subtropical ridge that is normally present north of the basin is being disrupted in part by Hurricane Lee. This pattern is supporting gentle to moderate winds. Seas of 7 to 10 ft in NE swell, and generated by Major Hurricane Lee, are moving into the NE Caribbean passages E of the Mona Passage. Seas of 5-7 ft are likely between the northern Leeward Islands and St. Croix. Elsewhere 3-5 ft seas prevail, except 2-3 ft in the NW Caribbean. For the forecast, Hurricane Lee will continue to disrupt the normal trade wind pattern through Thu night. The large NE swell across the adjacent Atlantic waters will gradually become N this afternoon and then N-NW tonight through Thu, moving through the Caribbean Passages and into the Caribbean waters between the Leeward Islands and the Mona Passage. Seas across these Caribbean Passages and waters will diminish significantly Thu through Fri as Lee lifts N of 31N. Moderate to locally fresh trade winds will then return to the Caribbean on Fri. ...ATLANTIC OCEAN... Please see the Special Features section for information about Hurricane Lee and Hurricane Margot. Outside of the weather conditions associated with the tropical waves and tropical cyclones, no significant convection is noted across the basin. Weak low pressure remains nearly stationary near 14.5N48.5W is producing a few showers. The most recent scatterometer satellite data indicated the cyclonic circulation related to this weak low with mainly gentle to moderate winds around it. A weak 1023 high pressure is near 40N49W. Gentle winds are noted elsewhere across the Atlantic outside of the areas near Lee and Margot, with combined seas of 5 to 7 ft in mixed swell across the trade wind zone. To the south of Lee, buoy observations are reporting seas of 6-7 ft in N-NE swell along the north coast of Puerto Rico. For the forecast west of 55W, Hurricane Lee is expected to maintain a slow NW motion through tonight, then begin a gradual turn toward the N on Wed and exit the area to the north of 31N Thu night. Lee will move to near 24.4N 66.2W this afternoon, near 26.6N 67.5W Wed afternoon, near 30.4N 68.0W Thu afternoon, and 32.9N 67.6W Fri morning. Lee will change little in intensity through Wed afternoon before beginning to slowly weaken. Large E to SE swell dominating the waters east of 78W will continue to propagate westward across the Atlantic, reaching the Florida and Georgia coasts Tue afternoon and evening. Large swell from Lee will dominate regional waters tonight through Fri. $$ Stripling