200 AXPZ20 KNHC 120911 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Sep 12 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 0600 UTC surface analysis and satellite imagery through 0830 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from the coast of Costa Rica near 11N86W to 15N95W to a 1010 mb low near 16N106W to 11N120W to 14N130W to beyond 13N140W. Scattered moderate to isolated strong convection is noted from 04N to 17N between 85W and 108W. Scattered moderate convection is noted from 07N to 14N between 108W to 139W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The remnant low of former tropical cyclone Kay is analyzed near 28N122W, just west of the Baja California offshore waters, with a central pressure of 1009 mb. The latest ASCAT shows gentle to moderate winds near the low center. Seas are 6-7 ft north of 26N between 121W and 126W. The low is forecast to drift southeast toward the Baja California offshore waters while weakening today. This system should become a trough by Tue while continuing to slowly drift southward over the next few days. Light to gentle variable winds are noted across the offshore waters of Baja California and in the Gulf of California. ASCAT data depicts an elongated low near 16N106W with moderate to fresh winds along it. Moderate to locally fresh winds are also noted off the coast of Jalisco. Moderate to fresh northerly winds are likely occurring in the Gulf of Tehuantepec. Seas are generally 5-7 ft across the Mexico offshore waters with 1-3 ft in the Gulf of California. Abundant deep layer tropical moisture is leading to scattered moderate to isolated strong convection across most the southwest Mexico offshore waters. For the forecast, winds across the Baja California offshore waters will increase moderate to fresh Tue night into Wed as high pressure builds across the area. A trough of low pressure located along the coast of southern Mexico is associated with a broad area of disorganized showers and thunderstorms. This system is forecast to interact and merge with another disturbance located farther west, and environmental conditions are expected to be generally conducive for additional development over the next several days. A tropical depression is likely to form by the middle to latter part of this week while the system moves slowly westward near the coast of southern and southwestern Mexico. This system has a low chance of formation in the next 48 hours and high chance in the next 5 days. This system will increase winds and seas across southern Mexico toward the latter part of the week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds are noted across the central American offshore waters. Gentle to locally fresh winds are noted off the southern Colombia offshores in addition to Ecuador and the Galapagos Islands. The latest ASCAT depicts fresh winds south of El Salvador, likely associated with convection in the area. Meanwhile, cross- equatorial long- period south to southwest swell continues to propagate through the forecast waters. Seas generally range 5-7 ft, with seas up to 8 ft south of the Galapagos Islands. Thunderstorms continue to move across the offshore waters of Costa Rica, Nicaragua and El Salvador. Some thunderstorms are also noted off the southern coast of Colombia. For the forecast, gentle to moderate winds will continue across the Central American offshore waters with locally fresh winds across the offshore waters of Galapagos Islands and Ecuador. Moderate seas are expected through most of the area through the next week. The cross- equatorial long- period south to southwest swell will persist through mid- week. Seas are expected to increase across the Ecuador and the Galapagos Islands offshore waters by Mon night into Tue. Seas will slowly subside later in the week. A very moist and unstable atmospheric environment will maintain active weather across most of the offshore waters through the period. REMAINDER OF THE AREA... Relatively weak high pressure is present over the area north of the monsoon trough and west of 125W. The related light gradient is allowing for gentle to moderate trade winds north of the monsoon trough and west of 105W where wave heights are generally 5-7 ft ft. Moderate to fresh southerly winds are south of the monsoon trough. Seas of 7-9 ft in long-period south to southwest swell are noted S of 12N between 93W and 123W. An area of 8 ft seas is noted by an altimeter pass near 14N135W. For the forecast, little change in marine conditions are expected over the next couple of days as the remnant low of Kay over the northeast part of the area gradually weakens to a trough west Baja California Norte. 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 seas will persist south of the monsoon trough. The long-period southerly swell continue to longer across most of the southern waters into mid- week. An area of 8-9 ft seas will linger near the southern Mexico offshore waters as a low pressure system may develop later in the week. The area of 8 ft seas near 14N130W will subside by tonight. $$ AReinhart