000 AXPZ20 KNHC 050836 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Nov 5 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 0830 UTC. ...SPECIAL FEATURES... Tropical Storm Pilar is centered near 10.6N 112.1W at 05/0900 UTC, moving west at 10 kt. Estimated minimum central pressure is 1000 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Numerous moderate to strong convection is noted within 90 of center in the northern semicircle. Peak seas are currently around 17 ft. Pilar will slow down on its westward motion over the next couple of days, and maintain a similar intensity, before moving more to the WNW and weakening into the middle of the week. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Pilar NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Gulf of Tehuantepec Gale Warning: Northerly gap winds continue through the Gulf of Tehuantepec in southern Mexico. The gales are due to cooler, drier air and high pressure over the Gulf of Mexico, and lower pressure farther south into the tropical Pacific. Seas are likely reaching 16 ft downstream in the Gulf of Tehuantepec, with seas in excess of 8 ft extending beyond 400 nm offshore. This gap wind event will diminish below gale force tonight into early Mon morning, but fresh to strong gap winds and rough seas will persist until Tue. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. Potential for heavy rainfall over Central America: A low pressure system that moved into northern Central America has weakened to a trough over the past several hours. However, clusters of showers and thunderstorms persist over much of Nicaragua, and may increase over Honduras, Guatemala and El Salvador later today. This rainfall could produce flash flooding, along with mudslides in higher terrain areas. Refer to the local weather services for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N86W to 07N85W to 08N100W, and from 08N115W to 1011 mb low pressure near 12N130W. The ITCZ extends from 11N132W to 07N140W. Scattered moderate convection is from 08N to 12N between 87W and 89W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the Special Features section above for details on the Gulf of Tehuantepec Gale Warning. Outside of the Gulf of Tehuantepec gap wind event, a ridge extends across the Baja California offshore waters from a 1021 mb high pres located near 29N133W. The pressure gradient between this system and a meandering trough over the Gulf of California supports gentle to moderate NW to N winds across the waters W of the Baja California peninsula with the exception of moderate to fresh winds in the vicinity of Punta Eugenia. Seas are generally in the 3 to 5 ft range. Moderate NW winds are evident in the Gulf of California, with 2 to 3 ft seas. Meanwhile, light to gentle winds are noted across the rest of the Mexico offshore waters. Seas range 4 to 6 ft in mixed swell. For the forecast, the gale force winds in the Tehuantepec region are expected to persist into early Mon morning. Associated rough seas will continue to propagate over the waters off eastern Oaxaca and western Chiapas into Mon. The winds and seas will continue to gradually diminish into Tue off southern Mexico. Looking ahead, a weakening cold front will approach Baja California Norte on Tue followed by fresh NW to N winds and moderate to rough seas. These marine conditions will reach the waters north of Punta Eugenia Tue night into Wed. Seas are forecast to propagate across the waters north of Cabo San Lazaro later on Wed. At the same time, high pressure situated over the Great Basin of the United States will bring moderate to fresh northerly winds across the Gulf of California Wed through Thu night. Seas are forecast to build to 4 to 6 ft within these winds. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate S-SW monsoonal winds prevail across the offshore waters with seas 4 to 6 ft. Seas range 8 to 9 ft across the offshore waters of Guatemala W of 93W due to the Tehuantepec gap wind event. For the forecast, expect large seas off Guatemala through tonight due to swell generated in the Tehuantepec region by gale force winds. Gentle to moderate winds and slight to moderate seas, primarily in SW swell, will persist elsewhere. ...REMAINDER OF THE AREA... Please refer to the Special Features section above for details on Tropical Storm Pilar. A ridge extends across the region north of 20N anchored by a 1021 mb high pressure near 29N133W, supporting moderate to fresh NE winds from 10N to 15N. Seas are to 8 ft within these winds. Elsewhere under the influence of the ridge gentle to moderate winds prevail with seas of 4 to 7 ft based on altimeter data. For the forecast, Pilar will move to 11.0N 113.2W this afternoon, 11.6N 114.2W Mon morning, 12.5N 115.1W Mon afternoon, weaken to a tropical depression near 13.8N 116.3W Tue morning, become a remnant low and move to 15.2N 117.5W Tue afternoon, and 16.5N 118.7W Wed morning. Pilar will dissipate early Thu. Elsewhere, a cold front will move into the waters north of 25N today, reach from 30N130W to 25N140W by Mon morning, and begin to weaken as it approaches Baja California Norte on Tue morning. A new swell event will follow the front building seas to 8 to 11 ft on Mon. As the front moves SE a large area of 8 to 9 ft seas will dominate most of the waters N of 20N W of 115W by Wed morning. $$ Christensen