000 AXNT20 KNHC 251749 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Sep 25 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 1700 UTC. ...SPECIAL FEATURES... Tropical Storm Philippe is centered near 17.3N 45.5W at 25/1500 UTC or 1010 nm E of the Northern Leeward Islands, moving W at 11 kt. Estimated minimum central pressure is 1000 mb. Peak seas are near 21 ft. A turn to the west-northwest is expected by tonight, and a northwestward motion is forecast to occur in a couple of days. Little change in strength is forecast during the next few days. Please, 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 Tropical Storm Philippe NHC Forecast/Advisory and Public Advisory, at www.hurricanes.gov, for more details. Eastern Tropical Atlantic (AL91): A tropical wave located several hundred miles west-southwest of the Cabo Verde Islands continues to produce disorganized showers and thunderstorms. Maximum winds are 20 kt and peak seas to 8 ft. Scattered moderate and isolated strong convection is noted from 07N-12N between 27W-33W. Environmental conditions are forecast to be conducive for gradual development, and a tropical depression is likely to form within the next few days as the system moves west- northwestward across the central tropical Atlantic. There is a medium chance of formation through 48 hours. ...TROPICAL WAVES... An east Atlantic tropical wave - Invest AL91 - has its axis along 31W between 03N-17N, moving westward at 10-15 kt. See SPECIAL FEATURES above for more information. A central Caribbean tropical wave has its axis along 77W, south of 20N, moving westward at 10-15 kt. Numerous moderate and scattered strong convection is noted from 10N-19N between 76W- 83W. ...MONSOON TROUGH/ITCZ... The monsoon trough leaves the coast of Mauritania near 17N16W and continues to a 1012 mb low pressure (AL91) near 10N31W and then to 08N32W. The ITCZ extends from there to 07N40W, where there is a break. The monsoon trough begins again at 16N46W to 10N53W, where the ITCZ then extends to the south of Venezuela near 09N61W. Scattered moderate and isolated strong convection is noted from 07N-12N between 27W-33W and from 09N-12N between 48W-53W. Scattered moderate convection is noted from 10N-14N east of 20W. ...GULF OF MEXICO... A surface trough extends from the Yucatan peninsula near 21N89W north-northeastward to 28N85W. Isolated moderate convection is noted south of 28N and east of 87W, as the surface trough and convection are being forced by a deep-layered trough over the same location. A weak 1015 mb high is centered near the Texas and Louisiana coast at 29N93W. Winds away from any thunderstorms are light to gentle with seas 2-3 ft. For the forecast, the surface trough over the southeast and south-central Gulf accompanied by scattered showers and thunderstorms will drift slowly into the western Gulf through mid week and dissipate. Meanwhile, weak high pressure will persist over the north-central and northeast Gulf. This pattern will support gentle to moderate NE to E winds and slight seas across the basin through the middle of the week. ...CARIBBEAN SEA... The Bermuda-Azores High well north of the Caribbean interacting with the 1008 mb Colombian Low to produce generally fresh trades over the central Caribbean and gentle to moderate elsewhere. Seas are 5-9 ft over the central Caribbean and 2-4 ft elsewhere. Numerous moderate and scattered strong convection is noted from 10N-19N between 76W-83W in association with the tropical wave near 77W. Winds and seas are higher in association with the thunderstorm activity. In the forecast, high pressure north of the area will continue to support moderate to fresh trade winds across most of the eastern and central Caribbean into mid week, with fresh to strong pulses off northwest Venezuela and northeast Colombia during mainly the overnight and early morning hours. Seas will build in mixed NE and E swell across the waters east of the Leeward Islands starting late Tue, ahead of Tropical Storm Philippe. Philippe is expected to turn NW before reaching 55W, and move into the central Atlantic. ...ATLANTIC OCEAN... Refer to the SPECIAL FEATURES section for details on Tropical Storm Philippe and Invest AL91. An expansive Bermuda-Azores High and associated ridge extends just north of our waters. Aside from higher winds near Philippe and Invest AL91, the trades are generally gentle to moderate (with seas 6-8 ft) in the central and eastern Atlantic and light to gentle (with seas 4-6 ft) in the western Atlantic. A surface trough extends from 25N65W to 28N63W with scattered moderate convection within 120 NM east of the trough axis, but no enhancement of winds or seas. Philippe will move to 17.6N 47.2W this evening, 18.1N 49.2W Tue morning, 18.9N 51.2W Tue evening, 19.9N 52.9W Wed morning, 21.1N 54.2W Wed evening, and 22.1N 55.4W Thu morning. Philippe will change little in intensity as it moves to near 23.7N 56.9W early Fri. Regardless of the exact position of the center later in the week, rough seas ahead of the storm can be expected east of 60W starting late Tue. Elsewhere, seas may build by Thu north of the Bahamas and east of Florida in NE swell. $$ Landsea