000 AXPZ20 KNHC 010301 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Nov 1 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 0150 UTC. ...SPECIAL FEATURES... Tropical Storm Pilar is centered near 11.9N 89.4W at 01/0300 UTC, moving north at 2 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Peak seas are currently around 17 ft. Scattered to numerous moderate isolated strong convection is noted from 05N to 15N between 83W and 95W. Beginning tomorrow into Thursday, Pilar is forecast to start moving westward to west-southwestward. On the forecast track, the storm may remain in close proximity to coastal Central America into tomorrow, but Pilar's core is forecast to remain offshore. Little change in strength is anticipated over the next day or so, followed by gradual weakening. Heavy rains from Pilar will produce flash and urban flooding, along with mudslides in areas of higher terrain of the Pacific coast of Central America from southern El Salvador, across southern Honduras, western Nicaragua into northern Costa Rica through Wednesday. Swells generated by Pilar are expected to continue affecting the Pacific coast of Central America during the next few days. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. 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 Storm Warning: Gale force N winds continue across the Gulf of Tehuantepec, and extend southward to near 13.5N, as strong high pressure is building across eastern Mexico behind a cold front in the Gulf of Mexico. Winds will increase to minimal storm force tonight through early Thu. Winds may fluctuate to just below storm force to minimal storm force at times, but the difference will be negligible. Gales will continue after Thu and gradually diminish below gale-force through Sat evening. Very large and dangerous seas of 12-24 ft will build with these winds, and also mix with swells generated by Pilar located SE of the area, resulting in confused and hazardous seas where they merge. Please read the latest NHC High Seas forecast at www.hurricanes.gov/marine for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from SW of Pilar near 09N100W to low pressure, Invest EP93, near 12.5N116W to 09N124W. The ITCZ extends from 09N124W to 07N140W. Scattered moderate isolated strong convection is noted from 10N to 15N between 113W and 118W, and from 06N to 09N between 120W and 128W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the Special Features section above for details on Tropical Storm Pilar, and on a Gulf of Tehuantepec Storm Warning. A tight pressure gradient continues over the Gulf of California region, producing fresh to strong NW-N winds in the central and northern Gulf, with moderate to fresh winds in the southern Gulf. Seas are 5-7 ft across the northern Gulf of California, and 4-6 ft S of there. Elsewhere, winds are mainly moderate or weaker. Seas are 4-6 ft. For the forecast, other than the Gulf of Tehuantepec Storm Warning, Pilar will move to 11.9N 89.5W Wed morning, 11.7N 91.0W Wed evening, 11.3N 93.2W Thu morning, 10.6N 96.0W Thu evening, 9.8N 98.9W Fri morning, and 9.4N 101.4W Fri evening. Pilar will change little in intensity as it moves to 9.0N 106.0W late Sat. Meanwhile, fresh to strong winds in the northern and central Gulf of California will diminish Wed while seas subside. Mainly gentle to moderate winds will prevail elsewhere. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please refer to the Special Features section above for details on Tropical Storm Pilar. Aside from Pilar, mainly moderate S-SW monsoonal winds prevail across the offshore waters with seas of 4-6 ft, except 5-7 ft offshore Ecuador. Scattered showers and thunderstorms are across the waters from Costa Rica westward as described above. For the forecast, Pilar will move to 11.9N 89.5W Wed morning, 11.7N 91.0W Wed evening, 11.3N 93.2W Thu morning, 10.6N 96.0W Thu evening, 9.8N 98.9W Fri morning, and 9.4N 101.4W Fri evening. Pilar will change little in intensity as it moves to 9.0N 106.0W late Sat. Elsewhere, mainly moderate monsoonal winds will prevail through the forecast period, locally fresh to strong in the Gulf of Panama by the end of the week. A storm-force gap wind event in the Gulf of Tehuantepec will generate very large NW swell moving into the offshore waters of Guatemala tonight through the end of the week. These large seas from the NW will combine with seas propagating away from Pilar to create very confused and hazardous boating conditions. ...REMAINDER OF THE AREA... Please refer to the Special Features section above for details on Tropical Storm Pilar. High pressure is centered just N of the area near 32N130W with a ridge south and southwestward across the waters N of the monsoon trough and ITCZ. Fresh winds to 20-25 kt surround a 1007 mb low pressure, Invest EP93, near 12.5N116W, where seas are 6-8 ft. Winds are moderate or weaker elsewhere, along with seas of 5-7 ft. For the forecast, Pilar will move to 11.9N 89.5W Wed morning, 11.7N 91.0W Wed evening, 11.3N 93.2W Thu morning, 10.6N 96.0W Thu evening, 9.8N 98.9W Fri morning, and 9.4N 101.4W Fri evening. Pilar will change little in intensity as it moves to 9.0N 106.0W late Sat. Meanwhile, Invest EP93 has changed little in organization since earlier today, and environmental conditions are forecast to become increasingly unfavorable for development during the next day or two while the low drifts generally northward. Winds will be moderate or weaker across the remainder of the open waters, increasing to moderate to fresh from 09N to 21N and W of 110W by the end of the week into the weekend, which will build seas to around 8 ft in that area. Little change in seas is forecast elsewhere. $$ Lewitsky