000 AXPZ20 KNHC 080339 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Nov 8 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: The combination persistent SW flow bringing rich, deep-layer moisture along with divergent flow aloft will support the potential for heavy rainfall across southern Central America into early next week. This may particularly impact Costa Rica, where rainfall amounts may be in excess of 20 inches (500 mm) through Tue. Rainfall amounts as high as 10 inches (250 mm) may impact Panama through Tue as well. 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 near the border of Guatemala and El Salvador near 14N90W to 1011 mb low pressure near 13N115W, to 1011 mb low pressure near 11N129W, to 10N140W. Scattered moderate to isolated strong convection is active with in 90 nm off the coast of Costa Rica and western Panama. Scattered moderate convection is also evident from 10N to 12N between 100W and 105W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A cold front is progressing southward through north-central Mexico. A tight pressure gradient due to the front and associated pronounced troughing near the Gulf of California along with high pressure west of Baja California continues to support fresh to strong NW to N winds from the northern to the central Gulf of California, with similar winds filtering through Baja California Norte passages. Seas are 4 to 7 ft north of 26N in the Gulf of California. Mainly gentle to moderate winds prevail across the remainder of the offshore waters of Mexico. Seas of 4 to 7 ft in mixed swell dominate the open waters, with 2 to 4 ft seas in the southern Gulf of California. For the forecast, fresh to strong NW to N winds will spread southward in the Gulf of California through early Sat, filtering through Baja California passages by late tonight. Seas will build to 7 to 10 ft from the central to the southern Gulf of California by late tonight. Moderate to fresh N winds will pulse in the Gulf of Tehuantepec beginning Sat night, then pulsing to fresh to strong Sun night and beyond. Mainly gentle to moderate winds will prevail elsewhere, possibly freshening offshore Baja California north of Cabo San Lazaro Mon night through Tue. Meanwhile, seas of 4 to 7 ft in the open waters are forecast to persist into early next week, building north of Cabo San Lazaro with the freshening winds Mon night into early Tue. Looking ahead, a significant and large NW swell event may arrive offshore Baja California by mid-week. ...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. Gentle to locally moderate winds are occurring across the Central and South American offshore waters, S to SW south of 11N and W to NW north of 11N, per recent ASCAT scatterometer data. A long-period S to SW swell is leading to seas of 6 to 8 ft offshore of Ecuador toward the Galapagos Islands. To the north, seas of 4 to 7 ft within S to SW swell are noted. For the forecast, winds will increase slightly to moderate to fresh south of 11N tonight, then pulsing to strong near Central America beginning Fri afternoon through early next week. These winds will support seas of 7 to 9 ft from mainly 02N to 10N through Sat. Mainly gentle to moderate breezes and seas of 4 to 7 ft with southerly swell will prevail elsewhere. ...REMAINDER OF THE AREA... The remnant low that was Fourteen-E has largely dissipated over the past several hours near 13N105W. A few showers and thunderstorms remain in that area, but there no longer appears to be a coherent low pressure area in favor of a broad and disorganized circulation along the monsoon trough. Two additional areas of weak low pressure are noted along the monsoon trough near 115W and 129W. A weak trough is analyzed farther north along 125W north of 22N. This is breaking up the subtropical ridge in the area, which in turn is allowing mostly gentle to moderate breezes farther south across the region. A large area of 7 to 9 ft combined seas persist over the tropical Pacific waters south of 15N between 95W and 130W, in a combination of northerly and southerly swell. Farther north, combined seas of 6 to 8 ft are evident north of 25N between 125W and 135W in northerly swell. Moderate combined seas are noted elsewhere. For the forecast, the weak lows along the monsoon trough will become less defined through the end of the week with winds across the open waters west of 120W mainly gentle to moderate through Sat. Winds are forecast to increase slightly to moderate to fresh north of the monsoon trough and west of 120W thereafter into early next week as high pressure builds in across those waters in the wake of a dying cold front passing by mainly north of 30N. Meanwhile, moderate to fresh winds will be south of the monsoon trough to about the Equator through the upcoming weekend with seas of around 8 ft there. Elsewhere for seas, the NW to N swell over the N-central waters will subside through tonight. A new set of NW swell will push southeast of 30N140W early Fri into early Sat, with seas of 7 to 9 ft west of a line from 30N120W to 20N130W to 10N140W by early Sun. Those seas will decay thereafter. Looking ahead, a larger and more significant set of NW swell may impact the NW and northern waters by late Mon night, spreading across much of the waters north of the monsoon trough and west of 115W through mid-week. $$ Christensen