000 AXPZ20 KNHC 240923 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Aug 24 2023 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... South of Southern Mexico: A broad area of low pressure located several hundred miles south of the coast of southern Mexico is producing some disorganized showers and thunderstorms. Environmental conditions appear favorable for gradual development of this system, and a tropical depression is likely to form within the next two to three days while it moves slowly to the northwest or north-northwest. Interests in southwestern Mexico should monitor the progress of this system. Currently, this system has a medium chance of tropical cyclone formation through 48 hours, and a high chance through 7 days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. Tropical East Pacific between 110W and 125W: Showers and thunderstorms are showing signs of organization in association with a low pressure system located well south of the southern tip of the Baja California peninsula. Environmental conditions are expected to be conducive for development of this system, and a tropical depression could form in the next few days while it moves west-northwestward across the tropical Pacific between 110W and 125W. Currently, this system has a medium chance of tropical cyclone formation through 48 hours, and a high chance through 7 days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 106W north of 05N, moving westward around 10 kt. Scattered moderate convection is noted ahead of the wave axis and north the monsoon trough from 11N to 14N between 105W and 110W. A tropical wave is along 120W, from 12N to 14N moving westward at 10 to 15 kt. Scattered moderate convection is observed from 12N to 14N between 120W and 122W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 12N86W to 1008 mb low pressure located near 10N99W to 1007 mb low pressure near 11N111W to 09N135W. The ITCZ extends from 09N135W to beyond 09N140W. Scattered moderate convection is along the coast of El Salvador, and from 13N to 15N between 95W and 98W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A recent scatterometer satellite pass indicated moderate to occasionally fresh NW winds off Baja California, between the subtropical ridge to the west and troughing over northwest Mexico. Seas off Baja California are estimated to be 5 to 7 ft. Farther south, fresh to strong gap winds are noted again over the Gulf of Tehuantepec. These gap winds are largely due to relatively lower pressure along the monsoon trough over the tropical eastern Pacific. Gentle breezes dominate the remainder of the area, with moderate combined seas over open waters in mostly SW swell. Scattered showers and a few thunderstorms are noted off Cabo Corrientes, and over the coast of western Guerrero. For the forecast, fresh to strong northerly gap winds will continue to pulse across the Gulf of Tehuantepec through tonight, then taper off Fri. Moderate to fresh NW winds will persist off Baja California north of Cabo San Lazaro through Fri between high pressure west of the region and lower pressure over Mexico. Winds and seas may increase off Guerrero and Michoacan late Fri through late Sat as the low mentioned on the special features develops and impacts the offshore waters. Regardless of development, heavy rainfall is possible over portions of southern Mexico. Please consult with local weather services for more information. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A recent scatterometer satellite pass verified the fresh to locally strong SW winds over the offshore waters from northern Costa Rica to El Salvador. Altimeter satellite data from farther offshore shows seas to 8 ft, likely reaching eastward into these offshore waters. Clusters of showers and thunderstorms are active over these waters as well. Light to gentle breezes persist elsewhere with moderate SW swell. For the forecast, the active monsoon trough will continue to support fresh SW winds and rough seas off Costa Rica, Nicaragua and El Salvador through tonight. These winds and seas will diminish Fri as the monsoon trough lifts north of the area. Elsewhere, gentle to moderate winds and moderate seas will prevail, primarily in SW swell. ...REMAINDER OF THE AREA... Showers and thunderstorms are starting to get a little more organized near 1007 mb low pressure mentioned in the Special Features section, centered along the monsoon trough near 11N111W. Ship observations and a recent scatterometer satellite pass indicates fresh to strong SW winds south of the monsoon trough and converging into the low. Recent altimeter satellite passes showed seas of 8 to 9 ft in the area of SW winds east of 115W, although this is largely due to longer period SW swell propagating through the region. Elsewhere, a relative weak pressure pattern is supporting moderate winds and seas across the basin. For the forecast, as mentioned in the Special Features, low pressure areas will likely develop along the monsoon trough and move to the northwest or west-northwest through early next week. The main impact area through Sun will be the tropical eastern Pacific from 05N to 20N between 110W and 125W. $$ Christensen