Eastern Pacific Tropical Weather Discussion
152 AXPZ20 KNHC 112118 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Fri Sep 11 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 16.8N 125.7W at 11/2100 UTC, moving west at 12 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are 20 ft within 150 nm NE quadrant of the center. Numerous moderate to strong convection is noted from 16N to 19N between 123W and 127W. Norbert is moving toward the west, and is expected to turn toward the west-northwest over the next couple of days. Some strengthening is forecast during the next 48 hours, and Norbert could become a hurricane this weekend. 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. Central and Western East Pacific (EP97): Showers and thunderstorms are becoming better organized in association with a broad area of low pressure located several hundred miles southwest of the southwestern coast of Mexico. Gradual development of this system is likely, and a tropical depression is expected to form late this weekend or early next week while it moves generally west- northwestward to westward over the central and western portions of the East Pacific. This system has a medium chance of tropical cyclone formation within the next 48 hours, and a high chance through 7 days. Refer to the latest NHC Tropical Weather Outlook at website - www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave has its axis along 113W, south of 20N, moving westward at 10 to 15 kt. A 1009 mb surface low (EP97) is along the wave axis near 13N113W. Scattered moderate to isolated convection is present from 11N to 16N between 107W and 115W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 08N100W to 11N110W, then continues SW of Norbert from 11N126W to 12N140W. In addition to the convection associated with T.S. Norbert and Invest EP97, scattered moderate to isolated strong convection is found from 04N to 08N E of 92W to the coast of Colombia, from 10N to 16N between 115W and 123W, and from 00N to 11N W of 125W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more information about Tropical Storm Norbert and Invest EP97. Recent scatterometer satellite pass provide observation of moderate to fresh northerly winds across the Gulf of Tehuantepec and downwind to about 14N. Seas in these waters are 5 to 7 ft. Elsewhere, high pressure of 1022 mb located 31N133W extends a ridge southeastward across the offshore waters of Baja California producing light to gentle winds. Fresh to locally strong southerly winds are over the northern Gulf of California. Moderate easterly winds and moderate seas are occurring west of the Revillagigedo Islands as Tropical Storm Norbert continues to pull away. Elsewhere in the Mexican offshore waters, moderate or weaker winds and slight to moderate seas prevail. For the forecast, Tropical Storm Norbert will move to 16.9N 127.2W Sat morning, strengthen to a hurricane near 17.3N 129.1W Sat afternoon, 17.7N 131.0W Sun morning, 18.1N 132.9W Sun afternoon, 18.3N 134.8W Mon morning, and weaken to a tropical storm near 18.4N 136.8W Mon afternoon. Norbert will change little in intensity as it moves to near 18.2N 141.2W Tue afternoon. As T.S. 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 Sun into early next week. Winds will also increase to fresh speeds across the northern Gulf of California early next week, likely 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 pulse again in the Tehuantepec region early next week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... High pressure north of the area is promoting fresh to strong easterly trade winds and rough seas across the Gulf of Papagayo region, extending downstream to near 89W. Elsewhere, moderate or weaker winds and moderate seas are prevalent. Scattered showers and thunderstorms are occurring off Panama and Colombia. Gusty winds and higher seas are likely occurring with these storms. 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 through early next week. Meanwhile, gentle to moderate southerly winds and moderate seas are expected over the waters between Ecuador and the Galapagos through at least the middle of 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 and Invest EP97. Away from the impacts of T.S. Norbert, moderate to locally fresh SE winds and rough seas are found south of 04N and west of the Galapagos Islands to about 130W. High pressure of 1022 mb located just north of area dominates the N waters, mainly N of 20N and W of 110W. Under the influence of this system, and away from Norbert, mainly moderate winds and moderate seas prevail, with the exception of light to gentle winds N of 21N and E of 118W to Baja California Peninsula. For the forecast, Tropical Storm Norbert will move to 16.9N 127.2W Sat morning, strengthen to a hurricane near 17.3N 129.1W Sat afternoon, 17.7N 131.0W Sun morning, 18.1N 132.9W Sun afternoon, 18.3N 134.8W Mon morning, and weaken to a tropical storm near 18.4N 136.8W Mon afternoon. Norbert will change little in intensity as it moves to near 18.2N 141.2W Tue afternoon. Elsewhere, a cross equatorial swell will persist over the next several days producing seas to 9 ft south of 04N. A tight pressure gradient will result in locally fresh N winds and rough seas in the NE waters late this weekend into early next week.