


Tropical Weather Discussion
Issued by NWS
Issued by NWS
195 AXPZ20 KNHC 180847 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Aug 18 2025 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. ...TROPICAL WAVES... The axis of a tropical wave is near 82W, north of 03N, moving west at 10-15 kt. No significant convection is evident near this wave axis. The axis of a tropical wave is near 99W, north of 05N, moving west at 10 kt. Nearby convection is described below in the Monsoon Trough/ITCZ section. The axis of a tropical wave is near 113W, from 04N to 17N, moving west at 10-15 kt. Nearby convection is described below in the Monsoon Trough/ITCZ section. The axis of a tropical wave is near 138W, from 03N to 17N, moving west at 10-15 kt. No significant convection is evident near this tropical wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 13N135W to 11N140W. Scattered moderate to isolated strong convection is evident from 09N to 11N, between 83W and 85W. Scattered moderate convection to isolated strong convection is evident north of 09N between 85W and 88W, north of 12N between 88W and 94W, and north of 15N between 97W and 105W. Scattered moderate convection is active from 09N to 12N between 100W and 110W, and from 17N to 20N between 111W and 116W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak ridging extends from high pressure centered over the north- central Pacific to near the southern tip of the Baja California Peninsula, with a surface trough over the Gulf of California. This pattern is supporting gentle to locally moderate NW breezes and moderate seas off Baja California. A recent scatterometer satellite pass indicated fresh to strong N gap winds pulsing across the Gulf of Tehuantepec. Light to gentle breezes and slight seas are noted elsewhere off southern Mexico. Gentle winds and slight seas are over the Gulf of California. For the forecast, the pressure gradient between a ridge west of the Baja California peninsula and a trough over the Gulf of California will support gentle to moderate NW winds with moderate seas west of the Baja peninsula through the end of the week. Farther south, fresh to strong gap winds over the Gulf of Tehuantepec will diminish this morning, but expect fresh gap winds to pulse again tonight. Light to gentle winds and moderate seas in SW swell will persist across the remainder of the Mexican offshore waters. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds dominate the offshore waters north of 05N while gentle to moderate winds are noted south of 05N. Moderate seas prevail across the discussion waters. For the forecast, light to gentle winds will prevail across the waters north of 05N through the week while gentle to moderate winds are expected south of 05N. Cross- equatorial southerly swell will propagate across the regional waters, keeping seas in the moderate range, except in the lee of the Galapagos Islands where slight seas are expected. ...REMAINDER OF THE AREA... Ridging prevails north of 20N. The pressure gradient between this area of high pressure along with lower pressure in the vicinity of the ITCZ is supporting moderate to locally fresh trade winds north of the ITCZ to 20N and west of 135W. Seas over these waters are in the 6-8 ft range. Gentle to moderate winds, and seas of 4-7 ft, prevail elsewhere north of the ITCZ/monsoon trough. Gentle to moderate winds, and seas of 5-7 ft, prevail south of the ITCZ/monsoon trough. For the forecast, the ridge will remain in place through the end of the week. Combined seas will be rough in pockets south of 10N and west of 130W before subsiding Mon. Another surge of southerly swell south of the monsoon trough is expected between 115W and 135W by midweek. Little change is expected elsewhere. $$ Christensen