000 AXPZ20 KNHC 080954 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Oct 8 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... Tropical Storm Lidia is centered near 16.4N 112.5W at 08/0900 UTC, moving north-northwest at 2 kt. Estimated minimum central pressure is 990 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Peak seas are around 23 ft with the 12 ft seas extending 180 nm in the southern semicircle and 120 nm in the northern semicircle. Numerous moderate to scattered strong convection is noted from 13N to 19N between 110W and 115W. Lidia will slowly move northward through today, followed by an accelerated northeastward motion on Monday and Tuesday. On the forecast track, the center of Lidia should approach the Islas Marias and the coast of west central Mexico on Tuesday. Some gradual strengthening is expected through early next week, and Lidia is forecast to become a hurricane by early Monday. Swells generated by Lidia will affect the west coast of Mexico and the Baja California peninsula for the next several days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. High to very high seas are expected across the SW Mexico offshore waters through early next week as Lidia approaches the coast. Potential Tropical Cyclone Sixteen-E is centered near 14.5N 100.7W at 08/0900 UTC, moving northwest at 6 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Peak seas are around 9 ft. Numerous moderate to scattered strong convection is noted from 12N to 19N between 100W and 105W. The system will have a slower northwestward to north-northwestward motion later today and continue through late Monday. On the forecast track, the center of the disturbance is forecast to approach the coast of southern Mexico within the watch area on Monday. Some strengthening is forecast during the next 48 hours, and this system could become a tropical storm late today. The system is expected to produce heavy rainfall across the states of Guerrero and Michoacan in southwest Mexico. These rains will likely produce flash and urban flooding, along with possible mudslides in areas of higher terrain near the coast. Rough to very rough seas are expected off the coasts of Oaxaca, Michoacan and Guerrero through Tue. 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 Lidia NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends off the coast of Nicaragua near 12N86W to 16N103W. The monsoon trough resumes W of Lidia near 12N115W to a 1010 mb low pressure near 11N127W to 10N140W. Scattered moderate to strong convection is noted from 08N to 19N between 86W and 105W. Scattered moderate convection is noted from 07N to 13N between 119W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the section above for details on Tropical Storm Lidia and Potential Tropical Cyclone Sixteen-E. Lidia is located about 500 nm WSW of Manzanillo, Mexico and 420 nm SSW of the southern tip of Baja California. Strong to tropical storm force winds are impacting the outer portions of the Baja California Sur and SW Mexico offshore waters. Rough to very seas extend as far north as 20N and as far east as 107W. Across the rest of the Baja California offshore waters, ridging extending over the region is bringing gentle to moderate winds. Seas range 5 to 7 ft within mixed swell. In the Gulf of California, the latest scatterometer data showed light to gentle winds. Seas are to 4 ft throughout most of the Gulf with seas around 5 ft near the entrance. Scattered thunderstorms are noted in Nayarit and Jalisco in addition to the entrance of the Gulf of California. In southern Mexico, fresh to strong N to NE winds prevail in the Gulf of Tehuantepec. Potential Tropical Cyclone Sixteen-E is also producing fresh to strong winds. As a result, seas range 8 to 9 ft in this area. Across the rest of southern and southwestern Mexico, gentle to moderate winds prevail with seas ranging 5 to 7 ft in mixed swell. Strong thunderstorms continue to impact the Gulf of Tehuantepec westward to Michoacan. For the forecast, Lidia will move to 17.1N 112.6W this afternoon, strengthen to a hurricane near 17.9N 112.3W Mon morning, 18.6N 111.3W Mon afternoon, 19.3N 109.4W Tue morning, 20.3N 106.9W Tue afternoon, and move inland and weaken to a tropical storm near 21.9N 103.7W Wed morning. Lidia will dissipate early Thu. Sixteen-E will move to 15.3N 101.2W this afternoon, 16.1N 101.5W Mon morning, 16.9N 101.6W Mon afternoon, inland to 17.9N 101.6W Tue morning, inland to 19.0N 101.5W Tue afternoon, and dissipate Wed morning. Dangerous marine conditions can be expected through early next week across the southern and southwestern Mexico offshore waters. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... With the monsoon trough lifted north of Nicaragua, gentle to moderate W to SW winds prevail across the Guatemala to Nicaragua offshore waters. Meanwhile, light to gentle winds prevail across the rest of the Central American offshore waters. Seas range 5 to 7 ft within S to SW swell. Gentle to moderate S winds prevail in the South American offshore waters. Seas range 4 to 6 ft in these waters within S swell. Strong thunderstorms continue to impact most of the Colombia offshore waters and the Gulf of Panama. Strong thunderstorms are also noted across most of the Guatemala, El Salvador, and Nicaragua offshore waters around the monsoon trough. For the forecast, the long-period S to SW swell will slowly subside across the Central American offshore waters today. Otherwise, the light to gentle winds will persist across the area through Mon. Expect moderate winds across the South American offshore waters on Tue through midweek. ...REMAINDER OF THE AREA... Refer to the section above for details on Tropical Storm Lidia. Scatterometer showed moderate to fresh winds continuing around the 1010 mb low pressure area near 11N127W. Altimeter also confirmed seas around 8 to 9 ft in this area. Moderate to fresh winds were also depicted by scatterometer south of Lidia, extending as far south as 07N. Otherwise, gentle to moderate south to SW winds are noted south of the monsoon trough with 5 to 7 ft seas. Farther south, southerly swell bringing 8 ft seas are noted S of the equator. North of the monsoon trough, light to gentle winds prevail under the influence of high pressure extending across most of the area. Seas range 5 to 7 ft. For the forecast, weak surface ridging will prevail W of 120W through Tue. The 8 ft seas and fresh winds around 129W will diminish by Mon night. The southerly swell in the southern forecast waters will subside today. A cold front will move across the northern waters Tue into Wed, bringing moderate to fresh winds and moderate seas. $$ AReinhart