075 AXPZ20 KNHC 090328 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Nov 9 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Excessive Rainfall Risk in Southern Central America: Persistent SW flow in the eastern Pacific region will bring rich, deep-layer moisture across southern Central America. This combined with a diffluent pattern aloft and the developing of a Central America Gyre (CAG) will support the potential for heavy rainfall across southern Central America into early next week. This weather pattern may particularly impact Costa Rica and Panama. This information is provided by the Weather Prediction Center's International desk team. Please refer to your national weather agency for details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 14N92W to 1010 mb low pressure near 10N102W, to 1011 mb low pressure near 13N114W, to 1011 mb low pressure near 11N137W to 11N140W. Scattered moderate convection is noted within 90 nm of the coast of Costa Rica and Panama, and from 08N to 10N between 102W and 105W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Low pressure persists over north-central Mexico. Along with weak ridging to the west, this pattern is supporting fresh to strong winds over the southern Gulf of California. An earlier scatterometer satellite pass and recent coastal observations indicate those fresh to strong NW winds are probably still active. Seas may be reaching 7 ft in this area. Recent ship observations also hint moderate to fresh NW winds off Cabo San Lazaro. Gentle to moderate winds and moderate seas persist elsewhere. For the forecast, the fresh to strong winds and associated moderate seas across the southern Gulf of California will diminish through Sat as the low pressure weakens. Farther south, fresh gap winds will pulse briefly across the Gulf of Tehuantepec Sun night. Gentle to moderate breezes slight to moderate seas will persist elsewhere through early next week. Looking ahead, building high pressure west of the region will support fresh NW winds off Baja California Norte late Mon into Tue. This will be followed by large NW swell, reaching Guadalupe Island by Tue night, then offshore of Cabo San Lazaro by Wed night. Farther south, fresh to strong gap winds are possible across the Gulf of Tehuantepec by Wed night. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please refer to the Special Features section for details on an Excessive Rainfall Risk in Southern Central America. Recent ship observations show an area of fresh to locally strong S to SW winds affecting the waters off Costa Rica and Panama where seas are in the 8 to 9 ft range with a component of SW swell. These winds are transporting abundant tropical moisture across southern Central America, supporting showers and thunderstorms within 90 nm of the coast. Farther south, linger SW swell to 8 ft may still be occurring off Colombia and Ecuador. Gentle to moderate breezes and moderate seas are noted elsewhere. For the forecast, moderate to fresh SW winds and large SW swell will continue impact the offshore waters of Panama into Sat, with moderate to fresh winds pulsing again across the offshore forecast waters of Costa Rica and western Panama Sun and Mon. Seas are forecast to build to 8 or 9 ft within these winds. Mostly moderate winds and seas will persist elsewhere. ...REMAINDER OF THE AREA... Buoy and ship observations, along with earlier scatterometer satellite data show mostly fresh SW flow across the tropical eastern Pacific east of 110W. Along with a component of SW swell, this pattern is supporting combined seas of 8 to 10 ft. Scattered showers and thunderstorms persist near the remnant low of Fourteen-E along the monsoon trough near 10N102W. Farther to the northwest, large swell is propagating into the region north of 25N and west of 135W. A trough persist along 130W north of 25N. This is breaking up the subtropical ridge and allowing mainly gentle to moderate winds to persist elsewhere, with combined seas of 5 to 7 ft in a mix swell. For the forecast, the NW swell of 8 to 9 ft will continue to push to the southeast, covering an area northwest of a line from Baja California Norte to 10N140W through Sun before decaying below 8 ft. A more substantial group of NW swell will follow by Mon night, with wave heights of 8 to 13 ft covering much of the region north of 10N and west of 115W through Thu. Farther to the southeast, the fresh to strong SW flow and associated seas will diminish in strength and areal extent through Sun night. $$ Christensen