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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Aug 26 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 0840 UTC. ...SPECIAL FEATURES... Tropical Storm Iselle is centered near 21.8N 123.5W at 26/0900 UTC, moving west-northwest at 8 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Peak seas are estimated near 20 ft. Convection from Iselle is sheared to the NE quadrant and extends from 21N to 27N between 118W and 123W. Iselle is moving toward the west- northwest near 9 kt, and this general motion is expected to continue over the next few days. Steady weakening is expected, and Iselle is forecast to become a post-tropical remnant low by early Thursday. Swells generated by Iselle will continue to affect the west coast of the Baja California Peninsula for a couple more days. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. Invest area EP93, is located well to the south of southwestern Mexico near 09N107W, and is producing a large area of heavy showers and thunderstorms. Scattered moderate to strong convection is ongoing from 03N to 16N between 89W and 116W. Environmental conditions are expected to support gradual development of this system, and a tropical depression is likely to form during the next couple of days while it moves west- northwestward at 10 to 15 kt, well offshore of Mexico. There is a high chance of tropical cyclone development within the next 2 and 7 days. A weak, elongated area of low pressure located well to the east-southeast of the Hawaiian Islands is producing disorganized showers and thunderstorms. Environmental conditions appear conducive for gradual development of this system, and a tropical depression is likely to form late this week or early this weekend while the system drifts to the northeast, then turns westward. There is a medium chance of tropical cyclone development within the next 2 and a high chance within 7 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 NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details on these two systems. ...TROPICAL WAVES... Former tropical wave near 110W got absorved into Invest Area EP93. See Special Features Section for further details. A tropical wave is crossing Central America, but the southern extent of its axis reach the E Pacific offshores. The wave axis is near 87W, and is moving westward about 15 kt. Scattered moderate to strong convection is offshore Costa Rica and Panama, from 02N to 10N between 80W and 89W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 07N93W to 09N100W to 11N115W. The monsoon resumes SW of Iselle near 14N125W and continues SW beyond 11N140W. Aside from the convection associated with the tropical wave and Invest EP93, scattered moderate convection is from 06N to 15N between 118W and 130W, and from 01N to 12N between 130W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for more information about T.S. Iselle and Invest EP93. Tropical Storm Iselle is near 21.8N 123.5W at 2 AM PDT, and is moving west-northwest at 8 kt. Maximum sustained winds are 45 kt with gusts to 55 kt, and the minimum central pressure is 996 mb. The proximity of Iselle continues to disrupt the ridge to its northwest, and into the Baja California Peninsula offshore waters. The gradient of the pressure between the ridge associated with a 1022 mb high near 35N130W and low pressure over Arizona is supporting gentle to moderate NW winds across the Baja California offshore waters N of Cabo San Lazaro as a scatterometer pass indicated. Seas are 4 to 8 ft in S-SW swell across the Baja California offshore waters and 4 to 5 ft across the SW Mexican offshores where winds are light to gentle. In the Gulf of California, light winds maintain slight seas. Otherwise, fresh to strong N to NE gap winds persist across the Gulf of Tehuantepec and downwind to about 14N with 5 to 8 ft seas. For the forecast, Iselle will move to 22.2N 124.6W this afternoon, become post-tropical and move to 22.8N 126.4W Thu morning, weaken to a remnant low near 23.5N 128.3W Thu afternoon, 23.8N 130.2W Fri morning, 24.3N 132.1W Fri afternoon, and dissipate Sat morning. Rough seas to 9 ft from Iselle affecting the outer Baja California Norte offshore waters will subside later today as Iselle continues to move NW away of the area. Elsewhere, fresh northerly gap winds will continue to pulse to strong speeds across Tehuantepec region during the overnight and early morning hours through the weekend, with seas occasionally building to 8 ft. Looking ahead, Invest EP93 has the potential to develop into a tropical depression during the next couple of days while it moves generally WNW at 10 to 15 kt, well offshore of Mexico. This system will likely follow a similar trajectory as Iselle, Fri through the weekend, and impact the outer offshore waters near the Revillagigedo Islands with strong winds and rough to very rough seas. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh NE to E gap winds are across the Papagayo region and downwind to near 91W, where seas are 5 to 7 ft. Gentle to moderate southerly winds and slight to moderate seas are S of 04N and between the Ecuador and the Galapagos Islands. Moderate or weaker winds are found elsewhere with slight to moderate seas in mixed swell. For the forecast, moderate to fresh NE to E gap winds will pulse to strong speeds over the Papagayo region each night through the weekend, building seas to around 8 ft. Moderate to fresh winds extending well downwind of Papagayo will impact the outer offshore waters of El Salvador and Guatemala through the end of the week. South of the monsoon trough, gentle to moderate S winds will prevail through the forecast period. ...REMAINDER OF THE AREA... Please see the Special Features section for more information about T.S. Iselle and Invest EP93. High pressure of 1022 mb located near 35N130W extends a broad ridge south and southeastward to approximately 121W, and drapes across Iselle. The pressure gradient between these features and low pressure associated with the monsoon trough is supporting moderate to locally fresh NE to E winds from 11N to 22N and W of 133W. Moderate to fresh SW winds are south of the monsoon W of 130W while moderate to fresh E winds accompany the Invest area EP93. Elsewhere, winds are moderate or weaker and seas moderate. For the forecast, an area of low pressure could form this weekend well to the south of southwestern Mexico. Environmental conditions appear favorable for some gradual development of this system, and a tropical depression could form by early next week while it moves westward to west-northwestward at 10 to 15 kt. There is a low chance of tropical cyclone development within the next 2 days and a medium chance through 7 days.