367 AXPZ20 KNHC 241500 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Tue Aug 24 2021 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 1500 UTC. ...SPECIAL FEATURES... Recently downgraded Tropical Depression Marty is centered near 20.6N 118.1W at 24/1500 UTC moving W at 10 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. No deep convection is currently present with Marty. Marty is forecast to become a remnant low this evening. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP3.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP3.shtml for more details. A broad area of low pressure located less than 200 miles offshore of Guatemala and southern Mexico continues to produce disorganized showers and thunderstorms. Environmental conditions are forecast to be favorable for gradual development of this system, and a tropical depression is likely to form by the middle to latter part of this week. The system is expected to move westward to west-northwestward at 10 to 15 kt this week, remaining offshore the coast of southwestern Mexico. This system has a high chance for tropical development within the next 48 hours. Refer to the National Hurricane Center Tropical Weather Outlook at www.hurricanes.gov for details. ...TROPICAL WAVES... The axis of a tropical wave is near 87W north of 01N, moving W at 10 to 15 kt. Associated convection is described in the section below. The axis of a tropical wave is near 95W north of 03N, moving W at 10 to 15 kt. Associated convection is described in the section below. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 13N95W to 16N108W to 11N140W. Scattered moderate isolated strong convection is noted from 03N to 08N east of 85W, from 08N to 15N between 85W and 100W, and from 08N to 13N between 115W and 133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section above for details on a developing area of low pressure offshore of Guatemala and southern Mexico. Light to gentle southerly winds prevail in the Gulf of California, with gentle to moderate winds offshore of Baja California outside of Marty. Moderate to fresh winds are being funneled along the coast and across the offshore waters of Guerrero and Michoacan. Seas across the offshore waters of Mexico outside of Marty are 4 to 7 ft, except 3 ft or less in the Gulf of California, and locally to 8 ft in the area of moderate to fresh winds. Fresh to strong N-NE winds are in the Gulf of Tehuantepec along with 5 to 7 ft seas. For the forecast, aside the area of disturbed weather off the coast of southern Mexico, gentle to moderate southerly flow will prevail in the Gulf of California. Fresh to strong N-NE winds will continue to pulse through midweek. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Refer to the Special Features section above for details on a developing area of low pressure offshore of Guatemala and southern Mexico. Scattered showers and isolated thunderstorms are continuing along the coast and offshore waters from Colombia northward under the influence of moist monsoonal winds. Light to gentle winds prevail offshore of Nicaragua northward. Moderate to locally fresh S-SW winds prevail south of the monsoon trough. Seas of 4 to 7 ft in mixed long period swell dominate the offshore waters. For the forecast, gentle to moderate winds will prevail north of the monsoon trough, pulsing to fresh in the Papagayo region. Moderate to fresh S to SW winds south of the monsoon trough will diminish somewhat by the end of the week. Long period SW swell will reach the coast of Central America today with a reinforcing set from the middle through the end of the week. REMAINDER OF THE AREA... Refer to the Special Features section above for details on Tropical Depression Marty. Aside from Marty, broad surface ridging dominates the waters north of the monsoon trough. Gentle to moderate N-NE winds prevail north of the monsoon trough, with mainly moderate to fresh southerly winds south of the monsoon trough, locally to strong. Seas of 4 to 7 ft dominate most of the waters, except near the locally strong winds where seas are 7 to 9 ft. For the forecast, trades north of the monsoon trough will gradually increase to moderate to fresh as the pressure gradient tightens. Otherwise, little change in marine conditions is forecast through the week. A set of northerly swell may push south into the area during the upcoming weekend with building seas. $$ AL