Eastern Pacific Tropical Weather Discussion
986 AXPZ20 KNHC 151643 CCA TWDEP Tropical Weather Discussion...Corrected NWS National Hurricane Center Miami FL 1605 UTC Sat Aug 15 2026 Corrected Tropical Waves section 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 1545 UTC. ...SPECIAL FEATURES... Tropical Depression Hernan is centered near 1 6.1N 134.9W, or about 1470 nm west-southwest of the southern tip of Baja California at 15/1500 UTC moving westward at 10 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 m. Shear has taken a toll on Hernan as latest satellite imagery depicts the system as a swirl of low to mid-level clouds with no deep convection. The depression is forecast to maintain its current motion for the next few days. Hernan is forecast to degenerate to a remnant low pressure area later today. 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...Corrected The axis of a tropical wave is along 85W north of 03N to inland central Nicaragua and eastern Honduras, It is moving westward at about 15 kt. Nearby convection is discussed in the ITCZ/monsoon trough section below. The axis of a tropical wave is near 103W south of 17N. It is moving westward at 10 to 15 kt. Numerous moderate to strong convection is seen from 07N to 13N between the wave and 110W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 1007 mb low pressure over northern Colombia at 10N75W westward to along the coast of southern Panama and through central Costa Rica, and continues to 10N84W to 10N99W and to 08N105W, where it transitions to the ITCZ to 05N115W to 08N123W and to 13N130W. Numerous moderate to strong convection is from 05N to 09N between 78W-88W. Scattered moderate to isolated strong convection is within 120 nm south of the trough between 95W-100W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to locally strong north gap winds are over the Gulf of Tehuantepec as was detected by overnight satellite ASCAT scatterometer passes. Moderate to locally fresh northwest winds are near the Pacific coast of Baja California. Elsewhere, winds are moderate or weaker. Seas are 5 to 7 ft over the Gulf of Tehuantepec, 4 to 6 ft over the remaining Pacific waters, and 1 to 3 ft over the Gulf of California. No significant deep convection is occurring over the Mexican offshore zones. For the forecast, the pressure gradient between high pressure over the Gulf of America and relatively lower pressure south of Mexico will continue to induce pulses of fresh to strong north winds, with speeds to near gale force over the Gulf of Tehuantepec well into next week. Moderate to fresh northwest winds are forecast off of the Baja California peninsula through Tue, with winds reaching strong speeds near and north of Punta Eugenia east of 117W. Elsewhere, winds and seas should remain rather calm 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 near the middle portion 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 northeast to east gap winds are over the Gulf of Papagayo region. Seas there are 6 to 8 ft. Elsewhere, winds are moderate or weaker across forecast waters, except locally fresh near the entrance to the Gulf of Guayaquil. Seas are 5 to ft in long-period southwest over the remainder of forecast waters. Numerous moderate to strong convection is over the waters off Panama and Costa Rica. For the forecast, the pressure gradient between high pressure over the western Caribbean and relatively lower pressure over Central America will lead to fresh to strong northeast to east 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 near 18N113W. 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 to 10 ft across those waters. Winds are moderate or weaker across the remainder of the waters north of the Equator with seas of 5 to 7 ft, except to 8 ft near the Equator between 100W and 116W. Moderate to fresh southeast winds and seas of 7 to 9 ft are south of the Equator. Any convection is described above in the monsoon trough/ITCZ section. For the forecast, Tropical Depression Hernan is forecast to become a remnant low near 16.2N 136.6W by this evening, then move to near 16.4N 138.9W Sun morning and to west of the area near 16.5N 140.9W by Sun evening. It is forecast to dissipate well west of the area by early Tue. Moderate to fresh southeast 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 near the middle portion of next week. Some gradual development of this system is possible, while the system moves westward or west- northwestward well south of Mexico.