000 AXNT20 KNHC 150602 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Fri Sep 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. Based on 0000 UTC surface analysis and satellite imagery through 0540 UTC. ...SPECIAL FEATURES... The center of Hurricane Lee, at 15/0600 UTC, is near 33.7N 67.6W. Lee is about 305 km/165 nm to the WNW of Bermuda; and 860 km/465 nm to the SSE of Nantucket in Massachusetts. Lee is moving toward the N, or 010 degrees, 12 knots. The estimated minimum central pressure is 957 mb. The maximum sustained wind speeds are 75 knots with gusts to 90 knots. Hurricane-force winds are: within 90 nm of the center in the NE quadrant; within 80 nm of the center in the SE quadrant; within 70 nm of the center in the SW quadrant; and within 80 nm of the center in the NW quadrant. Tropical storm-force winds are: within 300 nm of the center in the NE quadrant; within 300 nm of the center in the SE quadrant; within 200 nm of the center in the SW quadrant; and within 210 nm of the center in the NW quadrant. Sea heights that are 12 feet or higher are: 420 nm of the center in the NE quadrant; within 450 nm of the center in the SE quadrant; within 420 nm of the center in the SW quadrant; and within 450 nm of the center in the NW quadrant. The maximum sea heights are 27 feet. Expect: SW winds 20 knots to 33 knots, and sea heights from 13 feet to 17 feet from 27N to 31N between 59W and 74W. Expect also: winds 20 knots or less, and sea heights from 8 feet to 11 feet in mixed swell, from 22N northward between 51W and 81W, including in the Atlantic Ocean exposures. Swells that are being generated by Lee are affecting parts of: the Lesser Antilles, the British and U.S. Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, Bermuda, the east coast of the United States, and Atlantic Canada. It is likely for these swells to cause life-threatening surf and rip current conditions. Please, consult bulletins and charts that are from your local weather office for more details. Precipitation: scattered moderate to strong is from 32N northward between 62W and 73W. Isolated moderate to locally strong is within 60 nm on either side of 19N70W 20N68W 21N65W 25N62W 29N61W 31N61W. The center of Hurricane Margot, at 15/0300 UTC, is near 36.9N 38.9W. Margot is moving toward the ENE, or 070 degrees, 03 knots. The estimated minimum central pressure is 982 mb. The maximum sustained wind speeds are 65 knots with gusts to 80 knots. Large swell that is reaching 10 feet continues from 25N northward between 35W and 55W. Fresh and faster winds that are associated with Margot will remain from 30N northward N of 30N between 30W and 50W through tonight. 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 Lee and Margot NHC Forecast/Advisory and Public Advisories at www.hurricanes.gov for more details. ...Invest AL97 in the Central Tropical Atlantic Ocean... A 1008 mb low pressure center is near 13N41W. Scattered to numerous strong is within 310 nm of the center in the NW quadrant. Widely scattered moderate to isolated strong is within 410 nm of the center in the NE quadrant. The precipitation pattern continues to show some signs of organization. The environmental conditions are expected to be conducive for additional development. It is likely for this system to become a tropical depression during the next day or so. Its movement will be toward the west-northwest to northwest 10 to 15 mph, in the central tropical Atlantic Ocean. The chance of formation into a tropical cyclone during the next 48 hours is high. Expect E to SE winds 20 to 30 knots, and sea heights 8 feet from 12N to 16N between 33W and 44W. Expect the wind speeds to be 20 knots or less, and the sea heights to range from 8 feet to 10 feet in NE to E swell from 15N to 19N between 36W and 40W. Fresh NE winds now are within 520 nm to the south of 27N24W 23N42W. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the SW corner of Senegal, to 14N30W, to the 1008 mb INVEST AL97 low pressure center. Precipitation: scattered moderate to widely scattered strong is from 03N to 12N between 25W and 30W. Isolated moderate to locally strong is elsewhere from 03N to 12N between 20W and 50W. ...GULF OF MEXICO... A weak stationary front passes through the Florida Big Bend to the Florida Panhandle, to the coastal plains of Louisiana, through the upper Texas Gulf coast, beyond south central Texas. Precipitation: isolated moderate is from 28N northward. A 1013 mb high pressure center is near 24N85W. The GFS model for 250 mb and for 500 mb shows a trough in parts of the SE Gulf of Mexico. Precipitation: isolated moderate spans much of the area. Light to gentle winds cover much of the area. The sea heights are: 2 feet from the middle Texas Gulf coast into the southern half of the area; 1 foot elsewhere. A weak ridge across the northern Gulf will dominate the basin throughout the forecast period, supporting mainly light to gentle winds N of 24N and gentle to moderate winds S of 24N. Scattered thunderstorms can be expected across the western Yucatan and eastern Bay of Campeche each late afternoon and evening through the period. ...CARIBBEAN SEA... Hurricane Lee continues to move N away from the area. The surface pressure pattern is flat and weak. Broad and weak upper level cyclonic wind flow is in the central one-third of the area. Moderate to fresh NE winds are from 17N southward between 70W and 80W; and in the SE corner of the area. Moderate NE winds Honduras northward from 82W westward. Gentle winds cover much of the rest of the Caribbean Sea. The sea heights are: from 3 feet to 4 feet to the east of the line from the Colombia coastal waters to the border of Haiti and the Dominican Republic; and mostly 2 feet elsewhere, with the exception of 1 foot off the coast of SE Nicaragua. The monsoon trough is along 10N/11N from 74W in Colombia beyond Costa Rica. Precipitation: numerous strong is in the border areas of Colombia and Venezuela from 08N to 11N between 72W and 74W, and from 06N to 09N between 74W and 79W. Hurricane Lee is N of the area near 32.9N 67.6W at 11 PM EDT, and is moving north at 12 kt. Maximum sustained winds are 75 kt with gusts to 90 kt, and the minimum central pressure is 957 mb. Lee will move to 35.0N 67.3W Fri morning, 38.4N 66.6W Fri evening, 41.6N 66.6W Sat morning, move inland and weaken to a tropical storm near 44.3N 66.0W Sat evening, become extratropical and move to 47.0N 63.6W Sun morning, and 49.6N 59.1W Sun evening. Large swell affecting the NE Caribbean Passages will gradually decrease by late Fri, however moderate seas are forecast to prevail through early next week. Otherwise, moderate trade winds will dominate the central and portions of the SW Caribbean through Tue. Gentle to locally moderate winds are forecast elsewhere. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for details about Hurricane Lee, Hurricane Margot, and Invest AL97. An upper level cyclonic circulation center is near 23N53W. Precipitation: scattered moderate to widely scattered strong is from 21N to 26N between 50W and 54W. Isolated moderate to locally strong is in the remainder of the area that is from 14N northward between 39W and 60W. Moderate or slower wind speeds are in the remainder of the Atlantic Ocean. A 1022 mb high pressure center is near 33N28W. The sea heights of 8 feet or higher from 20N northward from 55W westward are related to Hurricane Lee. The sea heights range from 7 feet to 9 feet from 08N to 23N between 25W and 40W, and from 23N southward from 21W eastward. The sea heights range from 4 feet to 7 feet in much of the rest of the Atlantic Ocean. Hurricane Lee is near 32.9N 67.6W at 11 PM EDT, and is moving north at 12 kt. Maximum sustained winds are 75 kt with gusts to 90 kt, and the minimum central pressure is 957 mb. Lee will move to 35.0N 67.3W Fri morning, 38.4N 66.6W Fri evening, 41.6N 66.6W Sat morning, move inland and weaken to a tropical storm near 44.3N 66.0W Sat evening, become extratropical and move to 47.0N 63.6W Sun morning, and 49.6N 59.1W Sun evening. Lee will change little in intensity as it moves near 54.5N 42.5W late Mon. Long-period swell generated by Lee is expected to impact all waters north through east of the Bahamas through the weekend. High pressure will build across the area late Fri through Sun. Low pressure across the eastern Atlantic, AL97, is expected to approach the northeast part of the area Mon, possibly as a tropical cyclone, and track northwestward over that same area through Tue night leading to a significant increase in winds and seas. $$ mt/nr