000 AXNT20 KNHC 191815 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1815 UTC Fri Sep 19 2025 Tropical Weather Discussion for North America, Central America Gulf of America, 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 1745 UTC. ...SPECIAL FEATURES... Tropical Storm Gabrielle is centered near 21.9N 55.6W at 19/1500 UTC or 480 nm ENE of the Northern Leeward Islands, moving NW at 10 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Seas are peaking to around 22 ft just northeast of the center. Satellite imagery shows Gabrielle's center being mostly exposed under strong westerly shear causing a large area of numerous moderate to isolated strong convection to be located to the northeast of center roughly from 20N to 25N between 50W and 55W. Within this area of convection, relatively new convection, of strong intensity, has formed within 60 nm northeast of the center. Gabrielle is forecast to maintain its current motion through Sat, then a gradual turn toward the north-northwestward is expected by Sat night, followed by a northward motion by Sunday night. On the forecast track, the center of Gabrielle is expected to pass east of Bermuda Sun night and on Mon. Swells generated by Gabrielle are expected to reach Bermuda tonight and build through the weekend. 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 Gabrielle NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A far eastern Atlantic tropical wave has its axis near 20W from 03N to 16N. It is moving westward near 15 kt. Scattered moderate convection is within 60 nm either side of the wave from 06N to 09N, and within 180 nm west of the wave from 10N to 14N. A central Atlantic Ocean tropical wave has its axis near 36W from 06N to 21N, moving westward at 15 to 20 kt. Scattered moderate convection is within either side of the wave from 06N to 10N. A central Caribbean Sea tropical wave has its axis along 75W south of 21N to inland Colombia near 09N. It is moving westward at 15 to 20 kt. Scattered showers and thunderstorms are over the Windward Passage, and the wave and eastern Jamaica. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic near 19N16W, and continues southwestward to 10N25W to 08N30W and to 06N38W, where it transitions to the ITCZ to 05N50W. Aside from convection related to the tropical waves, scattered moderate convection is noted within 90 nm southeast of the trough between 21N-24W, and within 60 nm northwest of the trough between 23W-25W. ...GULF OF AMERICA... Relatively weak high pressure is over the basin. The related pressure is allowing for mostly light to gentle winds throughout. Seas as reported by buoy observations are 2 to 3 ft. Satellite imagery shows scattered showers and thunderstorms confined to the Bay of Campeche. Isolated showers and thunderstorms are some sections of the basin, mainly west of 87W and south of 25N east of 87W, including the eastern section of the Straits of Florida. For the forecast, the relatively weak high pressure in place will remain through tonight controlling the general weather pattern over the basin before shifting northeastward and weakening into next week. Unsettled weather will continue over the far southeastern Gulf through through tonight as ample moisture and a nearby trough remain in place. With Tropical Storm Gabrielle over the Atlantic lifting northward through Sun, Atlantic ridging will build westward along the northern Gulf early next week. ...CARIBBEAN SEA... Refer to the section above for details on the tropical wave moving across the basin. An upper-level trough continues to extend across the Atlantic from near Bermuda to Puerto Rico, then across the central Caribbean to a small upper-level low moving westward near 14N72W and to near northern Colombia. Water vapor imagery depicts a large upper-level low shifting westward near 26N65W. A very moist and unstable air mass present over the central Caribbean that is being acted upon by the trough is leading to scattered to numerous showers and thunderstorms north of 16N between 65W and 70W, including the Mona Passage and waters adjacent to the eastern and southwestern sections of Puerto Rico. In addition, an area of scattered moderate convection is seen south of 14N between 69W and 73W. Similar activity is confined to west of 85W to just inland the Yucatan Peninsula. Scattered showers and isolated thunderstorms are over some sections of Belize and in the Gulf of Honduras. A weak pressure gradient in place is providing for generally light to gentle easterly winds acros the sea along with slight seas as noted in the most recent scatterometer satellite data passes as well as in recent altimeter satellite data. For the forecast, the weak pressure gradient will tighten some over the weekend as Tropical Storm Gabrielle in the central Atlantic continues to lift north-nortwhestward, and at the same eastern and central Atlantic high pressure nudges westward. This should result in a slight increase of the gentle to moderate trades. Fresh to strong winds may pulse in the south-central portion of the basin Mon night beginning early Mon evening. through at least Tue night. ...ATLANTIC OCEAN... Refer to the sections above for details on Tropical Storm Gabrielle, and on the tropical waves across the eastern Atlantic. A cold front has pushed south into the northern waters extending from near 31N31W to weak low pressure of 1019 mb near 30N31.5W, and continues from the low pressure to 27N39W and northwestward to 29N42W, where it transitions to a stationary front to 31N46W. Isolated showers are near the low pressure and along the stationary front from 28N to 30N. Gentle to moderate northeast winds and seas are 5 to 7 ft are north of the frontal boundary. Elsewhere, high pressure of 1028 mb well north of area near 42W37W is building south-southwestward toward the aforementioned frontal boundary. A trough is over the far eastern Atlantic offshore western Africa from near 22N18W to 16N20W. No significant convection is occurring with this trough as it surrounded by a large area of late season Saharan Air layer (SAL). The pressure gradient in place is currently supporting mostly gentle to moderate easterly winds and moderate seas. For the forecast west of 55W, Tropical Storm Gabrielle is near 21.9N 55.6W at 11 AM EDT, and is moving northwest at 10 kt. Maximum sustained winds are 45 kt with gusts to 55 kt, and the minimum central pressure is 1004 mb. Gabrielle will move to 22.9N 56.9W this evening, 24.3N 58.5W Sat morning, 26.0N 59.8W Sat evening, strengthen to a hurricane near 27.8N 60.8W Sun morning, 29.8N 61.2W Sun evening, and then moving N of the area to 32.0N 60.9W Mon morning. Gabrielle will change little in intensity as it moves well away from the area to 37.5N 54.0W early Tue. A surface trough will persist off the SE U.S. coast to the northern Bahamas through at least the weekend enhancing convection in the vicinity. Otherwise, in the wake of Gabrielle, central Atlantic high pressure will build westward generally providing for light to gentle winds over the central and western portions of the area, and for gentle to moderate winds over the eastern portion. $$ Aguirre