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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat Aug 15 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 0730 UTC. ...SPECIAL FEATURES... Tropical Depression Hernan is centered near 16.4N 133.8W at 15/0900 UTC, moving west at 11 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Peak seas are around 10 ft or 3.0 m. Hernan is once again strongly sheered with scattered moderate isolated strong convection between 240 nm and 480 nm in the NE quadrant only. The depression is moving toward the west and this general motion is expected to continue through the next few days. Sow weakening is forecast during the few days, and Hernan is forecast to degenerate to a remnant low pressure area of Sat. 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 Hernan NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... The axis of a tropical wave is near 83.5W north of 06N to across portions of Costa Rica and continuing in the western Caribbean Sea along the Caribbean coast of Nicaragua, moving west around 15 kt. Nearby convection is discussed in the ITCZ/monsoon trough section below. The axis of a tropical wave is near 102W north of the Equator to near southwestern Mexico near the coast of Guerrero, moving west around 15 kt. Nearby convection is discussed in the ITCZ/monsoon trough section below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 1007 mb low pressure over northern Colombia at 10N75W to along the southern coast of Panama at 07N80W to 10N91W to 06.5N104W. The ITCZ begins there and extends to southeast of Tropical Depression Hernan at 13N127W. Numerous moderate scattered strong convection is noted from 05N to 09N between 77W and 85W. Isolated to widely scattered moderate and isolated strong convection is noted within 390 nm south of the monsoon trough between 85W and 98W, and within 300 nm either side of the ITCZ between 98W and 127W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to locally strong N gap winds are occurring over the Gulf of Tehuantepec as measured by recent ASCAT scatterometer passes. Moderate to locally fresh NW winds are near the Pacific coast of Baja California, with moderate to fresh SW winds in the northern Gulf of California north of 30N. Elsewhere, winds are moderate or weaker. Seas are 5-7 ft over the Gulf of Tehuantepec, 4-6 ft over the remaining Pacific waters, and 1-3 ft over the Gulf of California. No significant deep convection is occurring over the Mexican offshore zones. For the forecast, high pressure over the Gulf of America will continue to force pulses of fresh to strong N winds with locally near- gale speeds over the Gulf of Tehuantepec for the next several days. Additionally, moderate to fresh NW winds are forecast off of the Baja California peninsula through Mon night, locally strong at times. Moderate to fresh SE winds may move up the central to the northern Gulf of California Mon night and Tue. Elsewhere, winds and seas should remain quiescent until at least mid next week. Looking ahead, an area of low pressure could form several hundred nautical miles south of the coast of southern Mexico by the early to middle part of next week. Some gradual development of this system is possible thereafter while the system moves westward or west-northwestward well south of Mexico. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E gap winds are observed by recent OSCAT-3 scatterometer data over the Gulf of Papagayo region with seas 5-8 ft. Elsewhere, winds are moderate or weaker across forecast waters, except locally fresh near the entrance to the Gulf of Guayaquil. Seas are 4-7 ft in SW swell over the remainder of forecast waters. Scattered to numerous convection is present as described with the monsoon trough above over the waters off Panama and southern Costa Rica. For the forecast, high pressure over the W Caribbean will contribute toward fresh to strong E gap winds over the Gulf of Papagayo region through Sun night before weakening early next week with winds diminishing to moderate to fresh there. Moderate to fresh southerly winds will pulse south of the monsoon trough through Mon. Large southerly swell will impact the waters mainly from Ecuador to the Galapagos Islands through the next several days, largest by midweek. ...REMAINDER OF THE AREA... Please see Special Features section above for more on Tropical Depression Hernan. Surface ridging extends from 30N128W to 181N113W. Aside from conditions associated with Hernan, moderate to fresh winds are across the remainder of the waters from 15N to 26N to the west of 124W. Seas are 7-10 ft across those waters. Winds are moderate or weaker across the remainder of the waters north of the Equator with seas of 5-7 ft, locally 8 ft near the Equator between 100W and 116W. Moderate to fresh SE winds and 7-9 ft seas are found south of the Equator. Any convection is described above in the monsoon trough/ITCZ section. For the forecast, Tropical Depression Hernan will become a remnant low and move to 16.5N 135.5W this afternoon, 16.6N 137.8W Sun morning, 16.7N 139.9W Sun afternoon, moving west of the area to near 16.8N 141.9W Mon morning, 16.8N 143.9W Mon afternoon, and dissipate Tue morning. Moderate to fresh SE winds will prevail south of the Equator. Rough seas will pulse on either side near the Equator to the east of 130W through the next several days in persistent and reinforced southerly swells. Looking ahead, an area of low pressure could form well to the west-southwest of the southern tip of the Baja California Peninsula by the early to middle part of next week. Gradual development of this system is possible thereafter while it moves generally westward across the western portion of the east Pacific. Additionally, an area of low pressure could form several hundred nautical miles south of the coast of southern Mexico by the early to middle part of next week. Some gradual development of this system is possible thereafter while the system moves westward or west-northwestward well south of Mexico.