000 AXPZ20 KNHC 040917 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Jul 4 2024 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 0900 UTC. ...SPECIAL FEATURES... Offshore of Southern Mexico (EP91): A concentrated area of showers and thunderstorms is associated with an area of low pressure located a few hundred miles south of the southern coast of Mexico. The low pressure is analyzed near 16N105W with a central pressure of 1008 mb. Scattered moderate convection is noted from 15N to 18N between 104W and 107W. While this activity continues to show signs of organization, it is unclear if a well- defined center has formed with the system. Environmental conditions appear conducive for some additional development later today, and a short-lived tropical depression could form during over the next day or so. By Friday, the system is forecast to move over cooler waters and development after that time is not expected. The disturbance is forecast to move northward today and then turn northwestward by Friday, remaining offshore of the southwestern coast of Mexico. This system has a medium chance for tropical formation within the next 48 hours and 7 days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Costa Rica near 09N84W to low pres near 16N105W 1008 mb to 09N131W. The ITCZ extends from 09N131W to beyond 08N140W. Scattered moderate convection is noted from 08N to 16N between 87W and 97W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information on a broad area of low pressure that is well offshore southern Mexico with potential for tropical cyclone formation. Otherwise, a weak pressure gradient over the area. This is allowing for light to gentle winds over the offshore waters as confirmed by the overnight scatterometer data. Seas across the Baja California offshore waters range from 5 to 7 ft within mostly NW swell with southerly swell noted south of Cabo San Lucas. Across the SW and southern Mexico offshore waters, 6 to 8 ft seas are noted with 8 ft seas near EP91, within mostly S swell. In the Gulf of California, gentle to moderate southerly winds are present along with seas of 2 to 4 ft. Scattered showers and thunderstorms are over the offshore waters of Jalisco and Michoacan related to EP91. For the forecast, scattered showers and thunderstorms will continue over the offshore the coast of southern Mexico over the next few days due to EP91. Fresh winds and rough seas will also continue through tonight. Otherwise, the gradient between a surface trough along the Baja California Peninsula and high pressure west of the area will continue to support moderate to fresh southeast winds along the Gulf of California through the weekend. Fresh to strong north gap winds and rough seas are expected in the Gulf of Tehuantepec region tonight through Fri. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh south to southwest winds are present over the offshore waters of Costa Rica, Panama, and Colombia. Meanwhile, mostly gentle to moderate southwest winds are over the remainder of the offshore waters. Seas across the waters N of 08N are 5 to 6 ft range due to long-period south swell. S of 08N, seas are 5 to 8 ft within SW swell across the rest of the Central America and Colombia offshore waters. Seas are 5 to 7 ft in SW swell across the Ecuador and Galapagos Islands offshore waters. Scattered thunderstorms are noted across the Guatemala, El Salvador and Nicaragua offshore waters. Scattered thunderstorms are also noted in the Gulf of Panama and offshore Colombia. For the forecast, moderate to fresh winds will continue across the Central America offshore waters through Fri night, with moderate to rough seas with these winds. Winds are also expected to become moderate to fresh over the Galapagos Islands offshore waters Fri through Sat night, along with moderate to rough seas. Scattered showers and thunderstorms are expected over most of the forecast waters through the next few days. Gusty winds and locally rough seas may accompany some of the activity. ...REMAINDER OF THE AREA... Surface ridging extends southeastward from strong high pressure of 1032 mb that is located well north of the area. The ridge covers the waters north of 20N and west of 120W. The latest scatterometer data depicts mostly light to gentle winds north of the ITCZ and monsoon trough. Locally moderate winds are noted N of 20N and W of 130W. An area of seas 8 to 9 ft within N to NE swell is noted N of 27N between 125W and 137W. Otherwise, seas range 5 to 7 ft in this area. Meanwhile, south of the ITCZ and monsoon trough, gentle to moderate south to southwest winds are noted. Seas are 6 to 8 ft within S swell. For the forecast, expect for the moderate to fresh east to southeast winds south of the ITCZ and monsoon trough west of 100W through Fri, then expand beyond 100W through the weekend. Seas of 6 to 8 ft with these winds are forecast to subside slightly later Sat into Sun to 5 to 7 ft in long-period south swell. Elsewhere, fresh northwest to north winds west of the Baja California Norte offshore waters will develop Fri night and move west through the weekend. These winds will be accompanied by moderate seas. The 8-9 ft swell N of 26N will propagate westward through Fri night where seas will subside below 8 ft. $$ AReinhart