436 AXPZ20 KNHC 041559 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Oct 4 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 1200 UTC surface analysis and satellite imagery through 1540 UTC. ...SPECIAL FEATURES... Tropical Storm Lidia is centered near 14.8N 108.6W at 04/1500 UTC, or about 350 nm SW of Manzanillo, Mexico, moving north- northwest at 7 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Peak seas are currently around 13 ft. Numerous moderate scattered strong convection is noted within 180 nm in the NW semicircle and 60 nm SE semicircle. Scattered moderate isolated strong convection is noted elsewhere from 12.5N to 19N between 104W and 112W. A continued north-northwest motion with a reduction in forward speed is forecast during the next day or so. Beginning late Thursday, a much slower westward motion is expected. Some slow strengthening is forecast over the next few days. 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 from 11N86W to 14N102W, then continues W of T.S. Lidia from 13N113W to 1007 mb low pres near 12N124W to 10N140W. Scattered moderate isolated strong convection is noted from 04N to 12N between 77W and 91W, from 07N to 16.5N between 91W and 102W, and from 04N to 13N between 112W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the section above for details on Tropical Storm Lidia. Elsewhere, scattered moderate to strong convection is noted over the nearshore and offshore Mexico waters from Mazatlan, Sinaloa southward to offshore Manzanillo and offshore the Mexican state of Michoacan. Similar heavy showers and thunderstorms are over the offshore waters between Acapulco and Puerto Angel. Outside of T.S. Lidia, surface ridging prevails across the offshore waters of Mexico, along with winds of moderate or weaker. Seas are 5-7 ft in NW swell across the waters W of 110W including offshore Baja California, and 4-5 ft in mixed swell elsewhere in the open waters. The exception is near Lidia, where seas over 6 ft are occurring south of 16.5N and west of 107W. In the northern Gulf of California, seas are 1-2 ft, and 2-4 ft in the southern Gulf of California. For the forecast, Lidia will move to near 16N110W Thu morning, 16N111W Fri morning, 16N113W Sat morning, 16N114W Sun morning, and near 16N115W Mon morning. NHC is forecasting Lidia to be a 60 kt tropical storm Sat morning through Mon morning. Elsewhere, fresh to strong winds may pulse in the Gulf of Tehuantepec Fri night through Sun morning. Winds will be moderate or weaker elsewhere through Sat along with mainly moderate seas. Looking ahead, a large area of showers and thunderstorms located well south of the coast of Guatemala is associated with a trough of low pres. Environmental conditions are expected to be conducive for gradual development during the next several days, and a tropical depression is likely to form this weekend or early next week while the disturbance moves slowly WNW. This system could be located to the south of the Gulf of Tehuantepec by late in the weekend. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Mainly moderate SW winds are occurring to the south of the monsoon trough, locally fresh from 07N to 10N, west of 88W. Elsewhere, winds are moderate or weaker. Seas are 4-7 ft in S swell across the offshore waters, except for 6 to 8 ft near the Galapagos Islands. Scattered showers and isolated thunderstorms are occurring well offshore from Colombia northwestward through the Central American offshore waters. For the forecast, winds will be moderate or weaker across the offshore waters through most of the week, except for locally fresh SW winds from 06N to 10N, west of 87W through this evening. New long-period southerly swell will build seas slightly offshore Ecuador to the Galapagos Islands through tonight, with mainly moderate seas elsewhere. Looking ahead, a large area of showers and thunderstorms located well south of the coast of Guatemala is associated with a trough of low pressure. Environmental conditions are expected to be conducive for gradual development during the next several days, and a tropical depression is likely to form this weekend or early next week while the disturbance moves slowly west-northwestward. ...REMAINDER OF THE AREA... Refer to the section above for details on Tropical Storm Lidia. Elsewhere, an area of 1007 mb low pressure along the monsoon trough near 12N124W is producing disorganized showers and thunderstorms. Scattered moderate convection is noted from 08N to 13N between 119W and 128W. Moderate to fresh NE to ENE winds and seas of 7 to 8 ft extend from the low northward to 20N, between 121W and 129W. Mainly moderate winds prevail across the remainder of the open waters, except for some fresh S winds, south of 07N between 105W and 125W. Seas are 6-8 ft mainly in northerly swell across the waters N of 16N and W of 122W. Seas are 7-9 ft in southerly swell S of 08N between 100W and 127W. Seas of mainly 5-7 ft in mixed swell prevail elsewhere. For the forecast, Lidia will move to near 16N110W Thu morning, 16N111W Fri morning, 16N113W Sat morning, 16N114W Sun morning, and near 16N115W Mon morning. NHC is forecasting Lidia to be a 60 kt tropical storm Sat morning through Mon morning. Meanwhile, development of the low near 12N124W, if any, should be slow to occur while it moves little during the next couple of days. By this weekend, environmental conditions are forecast to become less conducive for further development. Elsewhere, winds of moderate or weaker will prevail across the remainder of the open waters through the next several days, locally fresh at times along and just N of the monsoon trough near any transient low pressure areas. The northerly swell across the northern waters will gradually decay through tonight. Meanwhile, southerly swell of 7-9 ft will wax and wane through the week and into the weekend from around 05N southward, decaying thereafter. $$ Hagen