Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Sep 13 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Tropical Storm Norbert is centered near 18.2N 132.7W at 13/1500 UTC, moving west at 10 kt. Estimated minimum central pressure is 1000 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Peak seas are 20 ft or 6.0 m. Numerous moderate to scattered strong convection is noted within 60 nm of the center. Norbert is moving toward the west, and this motion is expected to continue during the next few days. Some fluctuations in intensity remain possible for the rest of the day, followed by a gradual weakening trend after that. 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 Norbert NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Gale Warning south of Clarion Island (Invest EP97): An area of 1007 mb low pressure located several hundred nautical miles southwest of the southern tip of the Baja Peninsula near 17.5N116W continues to produce an area of disorganized showers and thunderstorms to the southeast of its center. Numerous moderate and isolated to scattered strong convection is noted within 300 nm in the SE quadrant and 540 nm in the SW quadrant of the low. Associated winds are currently 20 to 25 kt with seas of 8 to 10 ft. Environmental conditions are expected to be generally conducive for development, and a tropical depression is expected to form during the next couple of days while the system moves generally westward. For more information on this disturbance, including gale warnings, please see High Seas Forecasts issued by the National Weather Service. This system has a high chance of tropical cyclone formation within the next 48 hours. A Gale Warning is in effect with this system. Regardless of tropical cyclone development, winds strong winds with rough seas are expected to the south and southwest of Clarion Island into Mon. Refer to the latest NHC Tropical Weather Outlook at website - www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 98W from 03N to 15N to just offshore and southwest of Oaxaca, Mexico, moving west at around 20 kt. Associated convection is described below in the ITCZ/Monsoon Trough section. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N76W to 11N87W to 07N100W to 10N115W to 06N140W. In addition to the convection associated with T.S. Norbert and Invest EP97, scattered moderate convection is active from 03N to 12N to the east of 110W, and from 02N to 10N between 110W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more information about Tropical Storm Norbert and Invest EP97. Fresh NW winds and seas to six feet are likely ongoing off Cabo Corrientes, with fresh N gap winds across the Gulf of Tehuantepec. Elsewhere, and aside from the winds and seas already described near Clarion Island, gentle to moderate breezes and 3-5 ft seas prevail across Mexican offshore waters, with 1-3 ft seas in the Gulf of California. For the forecast, away from the impacts of Invest EP97, a ridge will build across the offshore waters of Baja California, bringing moderate to locally fresh NW to N winds through the early part of the week, locally strong Mon night. Expect fresh winds across the northern Gulf of California through the early part of the week due to the pressure gradient between the ridge and lower pressure over the Colorado River valley. Strong to near-gale N gap winds will pulse again in the Tehuantepec region beginning Mon night, strongest beginning mid-week, with building seas of 8 to 10 ft. Meanwhile, rough seas will build well offshore Baja California Norte tonight through Mon night. ...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 locally rough seas across the Gulf of Papagayo region, extending downstream to near 90W. Elsewhere, moderate or weaker winds and moderate seas are prevalent, except slight seas offshore Colombia and Panama. Convection continues to develop on either side of the monsoon trough. Gusty winds and higher seas are likely occurring near thunderstorms. For the forecast, the 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 Thu. Moderate to locally fresh N winds may pulse in the Gulf of Panama at night into early Thu. Meanwhile, gentle to moderate southerly winds and moderate seas are expected over the waters between Ecuador and the Galapagos through mid-week. Gentle 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 134W. High pressure located north of area dominates the waters north of 24N. Under the influence of this system, and away from Norbert and Invest EP97, mainly moderate winds and moderate seas prevail, except fresh northerly winds over the N-central waters extending from offshore Point Conception, California. For the forecast, Norbert will move to 18.6N 134.4W this evening, 19.0N 137.0W Mon morning, 19.4N 139.7W Mon evening, moving west of the discussion waters and into the Central Pacific basin at 19.7N 142.4W Tue morning, weaken to a remnant low near 19.8N 145.1W Tue evening, and dissipate Wed morning. 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 N-central/NE waters through the early part of the week.