000 AXPZ20 KNHC 010844 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 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 0600 UTC surface analysis and satellite imagery through 0600 UTC. ...SPECIAL FEATURES... Tropical Storm Pilar is centered near 12.2N 89.8W at 01/0900 UTC, moving northwest at 3 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 18 ft. Scattered to numerous moderate isolated strong convection is noted from 09N to 15N between 89W and 94W. Scattered moderate convection is noted from 05N to 09N between 83W and 98W. On the forecast track, Pilar will remain in close proximity to the coast of Central America through this morning, but the core of the storm is expected to remain offshore. Some gradual weakening is forecast during the next couple of days. 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 today. Swells generated by Pilar are expected to continue affecting the Pacific coast of Central America during the next couple of 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: Strong gale force N winds are across the Gulf of Tehuantepec per a recent ASCAT scatterometer pass and are expected to be minimal storm force for the rest of tonight through early Thu due to a very tight pressure gradient across the region in the wake of a cold front N of the area. Winds may fluctuate to just below storm force to minimal storm force at times, but the difference will be negligible. Gales will then continue for the remainder of Thu through early Sun. 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 well WSW of Pilar near 11N100W to low pressure, Invest EP93, near 12.5N115.5W to 06.5N135W. The ITCZ extends from 06.5N135W to beyond 04N140W. Scattered moderate isolated strong convection is noted from 06N to 09N between 121W and 129W, and from 07N to 09N between 136W and 139W. Scattered moderate convection is noted within 120 nm of EP93 in the SW quadrant. ...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 4-6 ft across the Gulf of California. Elsewhere, winds are mainly light to gentle with 4-5 ft seas in mixed SW and NW swell. For the forecast, other than the Gulf of Tehuantepec Storm Warning, Pilar will move to 12.1N 90.6W this afternoon, 11.7N 92.5W Thu morning, 11.0N 95.2W Thu afternoon, 10.2N 98.1W Fri morning, 9.6N 101.0W Fri afternoon, and 9.2N 103.5W Sat morning. Pilar will change little in intensity as it moves to 9.5N 108.5W early Sun. Meanwhile, fresh to strong winds in the northern and central Gulf of California will diminish later today with subsiding seas. Mainly gentle to moderate winds will prevail elsewhere, possibly increasing to fresh to strong from Punta Eugenia northward by early next week. ...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 12.1N 90.6W this afternoon, 11.7N 92.5W Thu morning, 11.0N 95.2W Thu afternoon, 10.2N 98.1W Fri morning, 9.6N 101.0W Fri afternoon, and 9.2N 103.5W Sat morning. Pilar will change little in intensity as it moves to 9.5N 108.5W early Sun. 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 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 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 12.1N 90.6W this afternoon, 11.7N 92.5W Thu morning, 11.0N 95.2W Thu afternoon, 10.2N 98.1W Fri morning, 9.6N 101.0W Fri afternoon, and 9.2N 103.5W Sat morning. Pilar will change little in intensity as it moves to 9.5N 108.5W early Sun. Meanwhile, the organization of Invest EP93 has not improved since yesterday, and the environmental conditions are forecast to become increasingly unfavorable for development during the next day or two while the low meanders over the central portion of the eastern Pacific basin. 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 tonight into the weekend, which will build seas to around 8 ft in that area. Little change in seas is forecast elsewhere, except in the far NW waters where seas may build to around 8 ft late in the weekend in new NW swell. Looking ahead, a larger set of NW swell may arrive and push SE of 30N140W early next week. $$ Lewitsky