295 AXPZ20 KNHC 242205 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Sep 24 2018 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 1800 UTC surface analysis and satellite imagery through 2115 UTC. ...SPECIAL FEATURE... A broad area of low pressure is analyzed as 1008 mb surface low near 14N105W. Numerous moderate isolated strong convection is observed within 120 nm NW semicircle of the low. Scattered moderate convection in bands are elsewhere from 09N to 18N between 99W and 110W. Fresh southwesterly monsoonal flow is well south of the low, across the tropical waters from 06N to 10N between 101W and 117W. Environmental conditions are expected to be conducive for development, and a tropical depression is likely to form within the next day or so while the system moves west-northwestward well off the coast of Mexico. There is still much uncertainty at this time, however for now expect fresh to strong winds, and building seas, to spread north across the offshore waters from 15N to 23N on Wed through Sat, with mixed swell, in the form of 8 to 16 ft seas. Higher winds are highly possible across the waters west of the Baja Peninsula over the remainder weekend. Refer to the East pacific tropical Weather Outlook under WMO/AWIPS headers ABPZ20 KMIA/MIATWOEP for additional information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 10N100W to a low pressure...possible tropical cyclone...near 14N105W to 11N110W to 11N125W to 10N136W. Numerous moderate isolated strong convection is in the Gulf of Panama and from 06N to 09N between 85W and 91W. Scattered moderate convection is elsewhere from 07N to 14N between 113W and 130W, and from 07N to 18N W of 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the Special Features paragraph above. Surface ridging to the west will continue to retract away of the region during the next few days as a surface low, with a high chance of becoming a tropical cyclone, tracks west-northwest. Gentle to moderate northwest flow is forecast west of the Baja California through Thu morning, then light to gentle winds are expected through Fri. Gulf of California: Gentle to locally moderate variable winds forecast across the gulf waters north of 30N through much of the period. Otherwise, light to gentle variable winds expected across the remainder gulf waters through the weekend. Gulf of Tehuantepec: Fresh to locally strong nocturnal drainage is forecast tonight with a strong event expected Sat morning. A low pressure is forecast to develop over Guatemala offshore waters on Thu along with fresh to strong winds. The low will move west to south of Tehuantepec on Friday where it is expected to slightly intensify. Seas are forecast to build to 14 ft over the weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to locally fresh east nocturnal drainage flow expected through Thu night with seas building to 8 ft. Light and variable winds are forecast elsewhere north of the monsoon trough which is meandering between 09N and 12N. Moderate southwest flow is forecast south of the monsoon trough. REMAINDER OF THE AREA... See the Special Features paragraph above. A broad ridge continues across the subtropics accompanied by moderate to locally fresh anticyclonic flow south of 23N west of 120W. $$ Ramos