Eastern Pacific Tropical Weather Discussion
530 AXPZ20 KNHC 160729 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Aug 16 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 0720 UTC. ...TROPICAL WAVES... The axis of a tropical wave is along 88.5W north of 02N near the Galapagos Islands to inland eastern El Salvador and western Honduras and continuing into the far NW Caribbean Sea, moving westward at around 15 kt. Nearby convection is discussed in the ITCZ/monsoon trough section below. The axis of a tropical wave is near 107.5W south of 17N, moving westward at around 15 kt. Nearby convection is discussed in the ITCZ/monsoon trough section below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 1008 mb low pressure over northern Colombia near 10N75W to 08.5N100W to 07N117W. The ITCZ extends from 07N117W to 08N125W to 05N140W. Scattered to numerous moderate isolated strong convection is noted from 02N to 13N between 77W and 94W, and from 02N to 09N between 94W and 104W. Isolated to widely scattered moderate to strong convection is noted from 01N to 18N between 104W and 135W, and from 00N to 08N between 135W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to near gale north gap winds are over the Gulf of Tehuantepec. Moderate to fresh northwest winds are near the Pacific coast of Baja California per recent ASCAT scatterometer data. Elsewhere, winds are moderate or weaker. Seas are 7 to 10 ft over the Gulf of Tehuantepec, 5 to 7 ft over the remaining open Pacific offshore waters, and 1 to 3 ft over the Gulf of California. No significant deep convection is occurring over the Mexican offshore zones, except some clusters inland to near the coasts of the Gulf of Tehuantepec and near Cabo Corrientes. 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 over the Gulf of Tehuantepec through Wed night, then moderate to fresh thereafter. Winds may reach near gale force at times through Tue night, while rough seas are also expected. Moderate to fresh northwest winds are forecast off of the Baja California peninsula through Tue night, with winds reaching strong speeds near Punta Eugenia. Elsewhere, mainly moderate or weaker winds and moderate seas are forecast. Looking ahead, an area of low pressure could form several hundred nautical miles south of the coast of southern Mexico around the middle portion of next week. Gradual development of this system is possible thereafter, and a tropical depression could form late next week or over the weekend while the system moves 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 per recent ASCAT scatterometer data. Seas there are 7 to 10 ft downwind to near 10N90W. Elsewhere, winds are moderate or weaker north of the monsoon trough, and moderate to fresh south of the monsoon trough, locally strong near the Gulf of Guayaquil. Seas are 4 to 7 ft in long-period southwest swell over the remainder of forecast waters, except to 8 ft near the Galapagos Islands. Very active convection is present near the monsoon trough as described above across much of the offshore waters, with locally higher winds and seas possible near any convection. 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 tonight before weakening with winds diminishing to moderate to fresh through Tue, then back to fresh to strong thereafter. 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 expected by around the middle portion of the week. ...REMAINDER OF THE AREA... The remnants of Hernan, low pressure of 1008 mb, are located near 16N137.5W. Nearby winds are 20 to 25 kt in the northern semicircle per very recent ASCAT scatterometer data, with seas of 8 to 10 ft. Scattered moderate isolated strong convection continues to flare where removed from the center between 90 nm and 180 nm in the NE quadrant. Moderate to locally fresh winds are found elsewhere from 15N to 23N between 130W and 140W, and from 08N to 21N between 118W and 130W. Moderate to fresh southerly winds are found south of the Equator. Moderate or weaker winds dominate the remainder of the waters. Seas are 7 to 10 ft south of about 02N between 90W and 121W, amd 5 to 7 ft across the remainder of the waters. For the forecast, 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 about 130W over the next several days in persistent and reinforced southerly swells. The remnants of Hernan and associated residual winds and seas will shift of 140W by this evening. Looking ahead, an area of low pressure could form several hundred nautical miles south of the coast of southern Mexico around the middle portion of next week. Gradual development of this system is possible thereafter, and a tropical depression could form late next week or over the weekend while the system moves west-northwestward, well south of Mexico. Additionally, an area of low pressure is expected to form well to the west-southwest of the southern tip of the Baja California Peninsula early next week. Environmental conditions appear conducive for gradual development of this system, and a tropical depression could form during the middle to latter portions of next week while it moves generally westward across the western portion of the east Pacific. Regardless of development, expect some increasing winds and seas with this area.