000 AXPZ20 KNHC 100315 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Nov 10 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 continue to bring abundant tropical moisture across southern Central America. This combined with a diffluent pattern aloft and the presence 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. Global models continue to show the CAG having a connection to the long moisture fetch from the eastern Pacific through next Thu. 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 14N91W to 1011 mb low pressure near 11N101W, to 1011 mb low pressure near 11N114W to 09N130W to 10N140W. Scattered moderate to isolated strong convection is noted within 60 nm of the coast of Nicaragua, Honduras, and El Salvador. Scattered moderate convection from 12N to 14N between 93W and 98W, and from 08N to 10N between 125W and 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A relatively weak ridge across the waters north of 20N is supporting gentle breezes across the region. Fresh NW winds that were active earlier across the central and southern Gulf of California have diminished. Wave heights across the open waters is 4 to 6 ft primarily in NW swell, with 2 to 4 ft in the Gulf of California. For the forecast, 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, moderate to fresh N winds are expected in the Tehuantepec region through Tue. Then, winds are predicted to increase to fresh to strong speeds Wed night through Thu night as a ridge establishes across the eastern slopes of the Sierra Madre Mountains in Mexico. ...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. Satellite-derived wind data from earlier today indicated moderate to fresh S to SW winds across the offshore waters of Panama, including the Gulf of Panama. These winds are transporting tropical moisture across southern Central America, now supporting scattered showers and thunderstorms across the area, currently closer to the monsoon trough in the offshore waters from Nicaragua to El Salvador. Wave heights to 8 ft persist in the waters off Costa Rica and western Panama due in part to the SW winds but also SW swell in the region. Gentle to moderate winds and moderate seas are noted elsewhere. For the forecast, moderate to fresh SW to W winds and seas of 6 to 8 ft will continue to impact the offshore waters of Costa Rica and western Panama through Mon. Gentle to moderate winds and moderate seas will persist elsewhere. ...REMAINDER OF THE AREA... Moderate to fresh SW winds and 7 to 9 ft seas persist over the tropical Pacific east of 110W, mainly from 05N to 10N. An earlier scatterometer satellite pass indicated fresh S to SW winds flowing into 1011 mb low pressure persisting along the monsoon trough near 11N100W. A second low pressure area is along the monsoon trough at 11N113W, with fresh S to SW winds also active near the southern periphery of the low. Farther north, large NW swell is propagating into the area from the north- central Pacific, to the northwest of a line from 30N125W to 20N140W with highest seas to 9 ft. A weak trough is analyzed between 125W and 130W north of 25N. This feature is disrupting the subtropical ridge normally in place across the region, and thus supporting mainly gentle to moderate breezes elsewhere across the basin, where combined seas are 4 to 6 ft primarily in NW swell. For the forecast, the NW swell event will continue to push to the southeast, covering most of the area north of 20N and west of 130W by tonight before decaying below 8 ft late on Sun. 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 as another swell event reaches the forecast region. This follows a weak cold front moving eastward across the waters north of 25N through mid week. By Thu, a strong high pressure building in the wake of the front will support increasing trade winds west of 110W. Farther to the southeast, the fresh to strong SW flow and associated seas will diminish in strength and areal extent through Sun night. $$ Christensen