020 AXPZ20 KNHC 050419 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Oct 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 0000 UTC surface analysis and satellite imagery through 0000 UTC. ...SPECIAL FEATURES... Tropical Storm Lidia is centered near 15.6N 109.4W at 05/0300 UTC, moving northwest at 6 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 14 ft. Numerous moderate scattered strong convection is noted within 390 nm in the NW semicircle and 30 nm in the SE semicircle. A general northwestward to north-northwestward motion with a reduction in forward speed is forecast during the next day or so. Beginning later 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 13N78W to 15N104W, then continues W of T.S. Lidia from 15N112W to low pressure near 12N126 to 11N140W. Scattered moderate isolated strong convection is noted from 06N to 19N between 90W and 107W, and from 11N to 14N between 122W and 128W. Scattered moderate convection is from 04N to 08N between 82W and 87W, and from 07N to 11N between 110W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the section above for details on Tropical Storm Lidia. Elsewhere, scattered moderate convection is noted over most of the Mexican offshore waters to the south of the entrance to the Gulf of California. Outside of T.S. Lidia, surface ridging prevails across the offshore waters of Mexico, along with winds of moderate or weaker. The exception is near Lidia, where fresh to strong winds prevail S of 18N and W of 107W. Seas are 5-6 ft in NW swell are across the waters W of 110W including offshore Baja California, and 4-6 ft in mixed swell elsewhere in the open waters. The exception is near Lidia, where seas are 6-9 ft S of 18N and W of 106W. In the northern Gulf of California, seas are 1-3 ft, and 2-4 ft in the southern Gulf of California. For the forecast, Lidia will move to 16.0N 109.8W Thu morning, 16.2N 110.4W Thu evening, 16.3N 111.1W Fri morning, 16.1N 112.0W Fri evening, 16.0N 112.8W Sat morning, and 16.1N 113.6W Sat evening. Lidia will change little in intensity as it moves to 16.5N 114.7W Sun evening, then 17.0N 115.0W Mon evening. 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, elongated 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. This system should be located to the south of the Gulf of Tehuantepec by Sunday and Sunday night. ...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 5-7 ft in S swell across the offshore waters, except for 6-9 ft between Ecuador and the Galapagos Islands. Scattered showers and isolated thunderstorms are occurring across much of the offshore waters from Colombia WNW. 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 88W through this evening. Long- period southerly swell will continue offshore Ecuador to the Galapagos Islands through early Thu, with mainly moderate seas elsewhere. Looking ahead, a large, elongated 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 1007 mb area of low pressure located about 1200 nautical miles southwest of the southern tip of the Baja California peninsula near 12N126W is producing disorganized showers and thunderstorms. Convection with that low is described above. Moderate to fresh NE to ENE winds and seas of 7 to 8 ft extend from the low northward to 20N, between 120W and 130W. Mainly gentle to moderate winds prevail across the remainder of the open waters, except for fresh S to SW winds S of 13N between 102W and 125W. Seas are 7-9 ft in southerly swell S of 11N between 95W and 132W. Seas of mainly 5-7 ft in mixed swell prevail elsewhere, except N swell north of 12N. For the forecast, Lidia will move to 16.0N 109.8W Thu morning, 16.2N 110.4W Thu evening, 16.3N 111.1W Fri morning, 16.1N 112.0W Fri evening, 16.0N 112.8W Sat morning, and 16.1N 113.6W Sat evening. Lidia will change little in intensity as it moves to 16.5N 114.7W Sun evening, then 17.0N 115.0W Mon evening. Meanwhile, development of the low embedded in the monsoon trough near 12N126W, 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. 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. Southerly swell of 7-9 ft will wax and wane through the week and into the weekend from around 09N southward, decaying thereafter. A weak cold front may drop SE through 30N140W early next week. $$ Lewitsky