Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Aug 24 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 0600 UTC surface analysis and satellite imagery through 0940 UTC. ...SPECIAL FEATURES... Tropical Storm Iselle is centered near 17.8N 116.2W at 24/0900 UTC, moving northwest at 10 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Peak seas are 20 ft. Numerous moderate to strong convection is noted from 14N to 20N between 112W and 120W. Iselle is moving toward the northwest near 12 kt and this motion is expected to continue through tonight, followed by a gradual turn toward the west-northwest on Tuesday. Some strengthening is expected over the next day or so, and Iselle could become a short-lived hurricane by late tonight. Gradual weakening is then forecast starting on Tuesday. Swells generated by Iselle will affect the west coast of the Baja California Peninsula beginning today. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. 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 Iselle NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Central East Pacific (EP91): A broad area of low pressure located well to the southwest of the southern tip of the Baja California Peninsula is producing some disorganized showers and thunderstorms. Environmental conditions could still support the development of a short-lived tropical depression during the next day or so while the system moves generally northward, before it becomes absorbed by Tropical Storm Iselle. This system has a medium chance for tropical cyclone formation through 48 hrs, and also through 7 days. Please refer to the latest NHC Tropical Weather Outlook at website: https://www.nhc.noaa.gov/text/MIATWOEP.shtml for more details on these systems. ...TROPICAL WAVES... A tropical wave is along 92W from 03N to 18N, moving westward at 15 kt. Scattered moderate isolated strong convection is noted from 02N to 08N between 90W and 98W. A tropical wave is along 103W from 02N to 18N, moving westward at 15 kt. Scattered moderate isolated strong convection is observed from 04N to 19N between 94W and 107W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 07N78W to 09N85W to 06N100W to 10N109W, then continues SW of Iselle from 11N121W to beyond 07N140W. Aside from the convection related to the tropical waves, Invest area EP91 and T.S. Iselle described above, scattered moderate isolated strong convection can be found from from 02N to 12N W of 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more information about T.S. Iselle and Invest area EP91. Tropical Storm Iselle is near 17.8N 116.2W at 2 AM PDT, and is moving northwest at 10 kt. Maximum sustained winds are 50 kt with gusts to 60 kt, and the minimum central pressure is 996 mb. Iselle has reduced the pressure gradient over the region and winds have diminished to light to gentle N of Cabo San Lazaro where seas now are slight to moderate in SE swell. Tropical storm winds and very rough seas associated with Iselle are affecting the outer offshore waters between Cabo San Lazaro and Cabo San Lucas. Moderate to fresh SE winds and moderate seas are ongoing across the Jalisco offshore waters while NW winds of the same magnitude are adjacent to the Michoacan and Guerrero, Mexico coasts. Seas over the SW offshores are moderate in SE swell. Otherwise, fresh to strong N gap winds persist across the Gulf of Tehuantepec and downwind to about 14.5N along with seas to 8 ft. For the forecast, Iselle will move to 19.0N 117.4W this afternoon, strengthen to a hurricane near 20.1N 118.9W Tue morning, weaken to a tropical storm near 20.9N 120.7W Tue afternoon, 21.5N 122.5W Wed morning, 21.9N 124.4W Wed afternoon, and 22.4N 126.3W Thu morning. Iselle will change little in intensity as it moves near 23.1N 130.1W early Fri. Moderate NW winds will resume along the Baja California offshore waters Tue night as Iselle moves NW away from the region. However, rough seas associated with Iselle are forecast to subside Wed. Fresh northerly gap winds will continue to pulse to strong speeds across Tehuantepec region mainly during the overnight and early morning hours through the upcoming weekend, with seas occasionally building to 8 ft. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E gap winds continue across the Papagayo region and downwind to near 90W, where seas are 6 to 8 ft. Moderate or weaker winds are found elsewhere, with moderate seas in SE swell. For the forecast, high pressure will persist over the eastern Gulf of America and northwestern Caribbean leading to fresh NE to E gap winds pulsing to strong speeds over the Papagayo region each evening and night through Fri night. Moderate to fresh winds extending well downwind of Papagayo will impact the outer waters offshore of El Salvador and Guatemala through the end of the week. South of the monsoon trough, gentle to locally moderate winds will persist through Fri night. ...REMAINDER OF THE AREA... Please see the Special Features section for more information about T.S. Iselle and Invest area EP91. High pressure of 1022 mb located N of the area extends a ridge southeastward into the northern forecast waters. Under the influence of this system, and outside of Iselle, moderate to locally fresh N to NE winds are observed from 10N to 25N and W of 120W. Fresh NE to E winds are seen from 10N to 15N W of 130W. Moderate or weaker winds and moderate seas in mixed swell prevail elsewhere. For the forecast, an area of low pressure is expected to develop well south of the southern tip of the Baja California Peninsula during the middle part of the week. Gradual development is expected thereafter, and a tropical depression is likely to form later this week or over the weekend while the system moves generally west-northwestward at 10 to 15 kt. Looking ahead, another area of low pressure could form well offshore of Central America late this week. Environmental conditions appear conducive for some gradual development of this system over the weekend while it moves westward to west- northwestward at 10 to 15 mph well offshore of southern Mexico. This system has a low chance for tropical cyclone formation through 7 days.