000 AXPZ20 KNHC 140352 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Sep 14 2022 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 0000 UTC surface analysis and satellite imagery through 0330 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Costa Rica near 10N85W to 14N98W to a 1009 mb low near 16N109W to 13N123W to beyond 10N140W. Scattered moderate to isolated strong convection is noted from 06N to 16N between 78W and 106W. Scattered moderate convection is noted from 06N to 15N between 188W and 133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Light to gentle variable winds prevail across the offshore waters of Baja California and in the Gulf of California. Seas range between 4-6 ft off of Baja California and 1-3 ft in the Gulf. Light to gentle variable winds are noted across most of the SW Mexico offshore waters with seas 5-7 ft in S to SW swell. In the outer Michoacan and Guerrero offshore waters, a 1009 mb low near 16N109W is supporting fresh SW winds and seas to 8 ft. Scattered showers and thunderstorms are observed across most the SW Mexican offshore waters, particularly in Michoacan to Oaxaca. For the forecast, winds across the Baja California offshore waters will increase moderate to fresh later on Wed and into Thu as high pressure builds across the area. A large area of disorganized showers and thunderstorms a couple of hundred miles off the coast of southern Mexico is associated with a trough of low pressure. Environmental conditions are expected to become more conducive for development, and a tropical depression is likely to form toward the end of the week while the system moves slowly westward near the coast of southern and southwestern Mexico. Expect increasing winds and building seas offshore southern Mexico late in the week. This system has a low chance of formation in the next 48 hours and high chance in the next 5 days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate SW to W winds are noted across the Central American and Colombia offshore waters with seas 5-7 ft in S to SW swell. Moderate to locally fresh southerly winds remain across the offshores waters of Ecuador and the Galapagos Islands with mostly 5-7 ft seas. Seas are up to 8 ft across the Galapagos Islands and Ecuador offshore waters S of 01N. A moist and unstable environment is leading to scattered showers and thunderstorms across the majority of the Central American offshore waters and off the Colombia coast. For the forecast, winds across the Central American offshore waters will increase to fresh toward the end of the week as broad low pressure south of southwestern Mexico organizes. Winds over the Galapagos Islands and Ecuador offshore waters will diminish to gentle to moderate by Wed and continue over the next few days. Cross- equatorial swell across the Ecuador and Galapagos Islands offshore waters will slowly subside by Thu night. A very moist and unstable atmospheric environment will help maintain active weather across most of the offshore waters over the next few days. REMAINDER OF THE AREA... Relatively weak high pressure remains over the area north of the monsoon trough and west of 120W. The related light pressure gradient is allowing for gentle to moderate trade winds north of the monsoon trough and west of 120W, with seas ranging 5-6 ft. Moderate to fresh southerly winds are south of the monsoon trough. Wave heights of 7-8 ft in long-period south to southwest swell are noted S of 15N between 102W and 112W. A trough extends across the northeastern waters with moderate winds near it with seas to 6 ft. Cross-equatorial southerly swell continues to linger across the southern waters S of 01S. For the forecast, the weak high pressure is expected to continue over the next few days, with gentle to moderate winds north of the monsoon trough. Moderate to fresh southwest winds and associated wave heights of 8-10 ft in southerly swell will continue south of the monsoon trough through the next few days. These winds will likely increase to strong speeds east of 110W later in the week as tropical cyclone genesis takes place offshore the southwestern coast of Mexico. Wave heights could build to near 12 ft near the strongest winds. The long-period cross- equatorial swell will continue through most of the week, with 8 ft seas subsiding by the weekend. $$ AReinhart