Eastern Pacific Tropical Weather Discussion
895 AXPZ20 KNHC 102127 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Sep 10 2026 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Tropical Storm Norbert is centered near 16.5N 120.5W at 10/2100 UTC, moving west at 12 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Peak seas are 15 ft within 90 nm NE quadrant of the center. Numerous moderate to scattered strong convection is noted within 60 nm of center. Scattered moderate to isolated strong convection is elsewhere from 15N to 18N between 117W and 119W. Norbert is moving toward the west, and this motion is expected to continue through Friday. A turn toward the west-northwest is forecast by Friday night. Gradual strengthening is forecast over the next few days. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Fourteen-E NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 96W north of 03N through SE Mexico. The wave is moving westward at about 15 kt. Scattered moderate to isolated strong conveciton is seen from 09N to 11N between 96W and 99W. A tropical wave has its axis along 111W north of 03N. It is moving westward at about 20 kt. Scattered moderate to isolated strong convection is observed from 10N to 17N between 102W and 112W. Fresh to locally strong E to SE winds and moderate seas are on the E side of the wave axis from 13N to 17N to about 107W based on scatterometer data. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 07N96W to 10N110W, then continues SW of T.S. Norbert from 11N120W to 07N130W to 11N140W. In addition to the convection associated with Norbert and the tropical waves, scattered moderate to isolated strong convection is noted from 03N to 07N between 78W and 88W, and from 00N to 10N W of 132W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Marine conditions are improving in the Revillagigedo Islands as T.S. Norbert continues to move westward and away from the islands. Moderate to fresh easterly winds and seas up to 6 ft are still noted in the vicinity of Clarion Island. Fresh to strong N gap winds continue across the Tehuantepec region and downwind to near 14N. Moderate to locally rough seas are with these winds. Light to gentle winds dominate the offshore waters of Baja California under the influence of a weak ridge, anchored by a 1017 mb high pressure centered near 30N127W. Light to gentle winds and moderate seas are present elsewhere across the remaining Mexican offshore waters. For the forecast, Norbert will move to 16.5N 122.5W Fri morning, 16.5N 124.9W Fri afternoon, 16.6N 127.1W Sat morning, 17.0N 129.0W Sat afternoon, 17.6N 130.7W Sun morning, and strengthen to a hurricane near 18.0N 132.4W Sun afternoon. Norbert will weaken to a tropical storm near 18.4N 136.1W Mon afternoon. As Norbert continues to move westward, a stronger ridge will build across the offshore waters of Baja California, bringing moderate to locally fresh NW to N winds by Sun into early next week. Winds will also increase across the northern Gulf of California Fri and Fri night, then again Mon and Mon night due to the pressure gradient between the ridge and the meandering trough that is in place in that area. Otherwise, fresh to strong N to NE gap winds will continue to pulse across the Gulf of Tehuantepec through early Fri. Looking ahead, showers and thunderstorms associated with a broad area of low pressure are located several hundred miles southwest of the southwestern Mexico coast. Gradual development of this system is expected, and a tropical depression is likely to form by early next week while it moves generally west-northwestward over central and western portions of the East Pacific. This system has a high chance of tropical cyclone formation through 7 days, and a low chance through 48 hours. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Recent scatterometer data provide observations of fresh to strong NE to E winds across the Papagayo region and downwind to near 90W. Moderate to rough seas are within these winds. Gentle to moderate southerly winds are across the offshore waters between Ecuador and the Galapagos Islands along with moderate seas in SW swell. Moderate to fresh SE to S winds are evident just W of the Galapagos Islands. Otherwise, moderate or weaker winds with slight to moderate seas prevail elsewhere. Higher winds are noted near thunderstorms along the monsoon trough. For the forecast, a ridge north of the area will continue to support pulsing fresh to strong easterly winds, and moderate to rough seas across the Papagayo region, mainly at night, through Mon night. Seas are forecast to build to 8 or 9 ft with the strongest winds. Meanwhile, gentle to moderate southerly winds and moderate seas are expected over the waters between Ecuador and the Galapagos through early next week. Moderate or lighter winds and moderate seas in long period SW swell are forecast elsewhere. ...REMAINDER OF THE AREA... Please, see the Special Features section for more information about Tropical Storm Norbert. Aside from T.S. Norbert and the tropical waves previously mentioned, a surface trough is analyzed from 22N131W to 13N132W. Recent scatterometer data indicate the wind shift associated with the trough, with moderate to fresh winds near the northern end of it. A ridge dominates the waters N of 20N and W of 110W. Gentle to moderate winds and moderate seas are noted under the influence of the ridge, with the exception of light to gentle winds N of 27N and W of 130W as well as N of 20N E of 118W to the coast of Baja California. Moderate or weaker winds along with seas of 5 to 7 ft are over the remainder of the eastern Pacific forecast region. For the forecast, Tropical Storm Norbert will move to 16.5N 122.5W Fri morning, 16.5N 124.9W Fri afternoon, 16.6N 127.1W Sat morning, 17.0N 129.0W Sat afternoon, 17.6N 130.7W Sun morning, and strengthen to a hurricane near 18.0N 132.4W Sun afternoon. Norbert will weaken to a tropical storm near 18.4N 136.1W Mon afternoon.