000 AXPZ20 KNHC 070928 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 928 UTC Fri Aug 7 2020 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 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 0900 UTC. ...TROPICAL WAVES... A tropical wave axis is along 93W/94W, from 03N to the Gulf of Tehuantepec, moving westward at 15 kt. Scattered moderate to isolated strong convection is noted within 120 nm of the coast from El Salvador to Oaxaca. A tropical wave axis is along 132W/133W south of 18N, moving westward at 15 to 20 kt. No significant convection is noted with this wave axis. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends westward from 08N78W across Panama and Costa Rica to 11N103W to 10N130W. The ITCZ extends from 10N130W to beyond 10N140W. Scattered moderate convection is occurring within 90 nm south of the monsoon trough axis between 93W and 95W, between 122W and 127W, and between 105W and 108W, and between 132W and 134W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent scatterometer data confirmed fresh winds over much of the waters off Baja California north of Punta Eugenia. These winds are active between high pressure west of the area and lower pressure over Mexico. Gentle to moderate northerly flow continues from Punta Eugenia southward to Cabo San Lazaro, and light to gentle winds are noted south of Baja California Sur and off the southwestern coast of Mexico. Gentle to moderate SE winds continue along the Gulf of California. Fresh NW winds will prevail across the waters N of Cabo San Lazaro through Sun, then diminish early next week. Fresh northerly winds will pulse for the next several nights across the Gulf of Tehuantepec. An area of low pressure is expected to develop south of Mexico later in the weekend in association with a tropical wave presently moving through the Gulf of Tehuantepec. Environmental conditions are forecast to become increasingly conducive for development, and a tropical depression is likely to form early next week while the system moves generally west- northwestward, roughly a couple of hundred miles offshore of southwestern Mexico and Baja California Sur. This area has a high chance of tropical cyclone formation during the next five days. Expect increasing winds and seas over portions of the offshore waters between Acapulco and Puerta Vallarta from late Sat into early Mon in association with this system before impacting the Revillagigedo Islands through Tue. Please see the latest eastern North Pacific Tropical Weather Outlook for more information. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... A few showers and thunderstorms are active this morning off the coasts of El Salvador and Guatemala, due in part to a tropical wave passing through the region as well as overnight drainage flow near the coast. Earlier scatterometer data indicates moderate southerly winds prevail south of the monsoon trough. Regional wave heights remain 4-6 ft based on recent altimeter passes. The moderate southerly winds will persist south of the monsoon trough for the next several days. Moderate to fresh winds will pulse across the Gulf of Papagayo region tonight and Sat night, then diminish into early next week. Long-period southerly swell is building seas near the Galapagos Islands will propagate northward through this weekend. REMAINDER OF THE AREA... The subtropical ridge extends across the waters north of 20N. Recent scatterometer data from around 05 UTC indicated a few areas of fresh trade winds close to the monsoon trough/ITCZ, and gentle to moderate breezes farther north. Earlier altimeter data indicated seas reaching to 8 ft in the area of fresh trade winds west of 135W. Little change in marine conditions is expected in this region over the next several days. Farther south, generally moderate southerly flow is noted across the forecast waters south of 10N. Long-period southerly swell crossing the equator will continue to propagate northward through this weekend. Combined seas are expected to reach 8 ft south of the equator this morning. An area of freshening monsoon flow is expected between 100W and 115W tonight into Sat, which combined with southerly swell will likely build seas to 8 ft. Please see the latest eastern North Pacific Tropical Weather Outlook for more information about the high potential for tropical cyclone formation offshore of southwestern Mexico during the next five days. $$ Christensen