Eastern Pacific Tropical Weather Discussion
200 AXPZ20 KNHC 240408 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 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 0000 UTC surface analysis and satellite imagery through 0350 UTC. ...SPECIAL FEATURES... Tropical Storm Iselle is centered near 17.1N 115.3W at 24/0300 UTC, moving northwest at 10 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Peak seas are 17 ft. Numerous moderate to strong convection is noted from 11N to 20N between 112W and 120W. Iselle is moving toward the northwest near 12 kt and this motion is expected to continue through Monday, followed by a gradual turn toward the west-northwest on Tuesday. Some strengthening is forecast during the next day or two, and Iselle could become a strong tropical storm Monday night or early Tuesday. Swells generated by Iselle will affect the west coast of the Baja California Peninsula beginning Monday. 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): Disorganized showers and thunderstorms are persisting with a broad area of low pressure located well to the south-southwest of the southern tip of the Baja California Peninsula. Environmental conditions could support the development of a short-lived tropical depression during the next day or so 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 89W from 02N to 20N moving westward at 15 kt. Scattered moderate to isolated strong convection is noted from 03N to 16N E of 98W. A tropical wave is along 102W N of 03N into Mexico, moving westward at 15 kt. Scattered moderate to isolated strong convection is observed from 08N to 19N between 93W and 107W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N84W to 12N110W then continues SW of Iselle from 12N120W to 08N130W to beyond 07N140W. Aside from the convection related to the tropical waves, Invest area EP91 and T.S. Iselle described above, scattered moderate to isolated strong convection can be found from from 01N to 12N W of 125W. ...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 17.1N 115.3W at 8 PM PDT, and is moving northwest at 10 kt. Maximum sustained winds are 45 kt with gusts to 55 kt, and the minimum central pressure is 999 mb. A ridge continues to dominate the offshore forecast waters of Baja California Norte supporting gentle to moderate NW winds and moderate seas. Strong winds and rough seas associated with the outer periphery of T.S. Iselle are affecting the Revillagigedo Islands, particularly Clarion Island. Moderate to fresh SE to S winds are in the Gulf of California N of 25N with slight seas. Fresh to strong N gap winds persist across the Gulf of Tehuantepec and downwind to about 14.5N. Seas are 6 to 8 ft with these winds. For the forecast, Iselle will move to 18.1N 116.4W Mon morning, 19.4N 117.8W Mon evening, strengthen to a hurricane near 20.4N 119.6W Tue morning, weaken to a tropical storm near 21.0N 121.4W Tue evening, 21.5N 123.1W Wed morning, and 21.9N 125.1W Wed evening. Iselle will change little in intensity as it moves near 22.8N 128.8W late Thu. A ridge will persist between Baja California and Iselle through about midweek supporting gentle to moderate NW to N winds north of Cabo San Lazaro. Stronger winds and higher seas are expected across the forecast zone between Cabo San Lazaro and Cabo San Lucas, including the Revillagigedo Islands, due to the proximity of Iselle. The forecast calls for storm conditions in the Revillagigedo Islands tonight, and storm conditions possible in the Revillagigedo Islands and the forecast zone between Cabo San Lazaro and Cabo San Lucas on Mon. Fresh northerly gap winds will continue to pulse to strong speeds across Tehuantepec region mainly during the overnight and early morning hours through the next several days, 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 SW 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. Additional pulses of long period SW swell will continue to propagate across the area with moderate to locally rough seas. ...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 to offshore of Baja California Norte. Under the influence of this system, and outside of Iselle, moderate to locally fresh N to NE winds are observed N of 15N and W of 120W. Fresh NE to E winds are seen from 10N to 15N W of 125W. 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 toward the middle portion of the week. Some slow 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. Looking ahead, another area of low pressure could form well offshore of Central America late this week. Environmental conditions appear favorable for gradual development over the weekend as the system 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.