000 AXPZ20 KNHC 180351 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Nov 18 2024 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 0345 UTC. ...SPECIAL FEATURES... Eastern Pacific Swell Event: Long-period NW swell has reached the outer offshore waters of Colima, Mexico. Seas this afternoon. Seas have subsided to 8-10 ft across the Baja California Norte offshore waters and to 8-12 ft across the Baja California Sur and Jalisco offshore waters. This set of swell will continue to decay, with seas dropping below 12 ft late tonight. Another set of long-period NW swell is forecast to enter the offshore and adjacent waters N of Punta Eugenia Mon night. Seas will build to 14 ft and subside below 12 ft Tue evening. For more details, please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https//www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from low pressure near 19N106W 1007 mb south-southeastward to 16N105W and southwestward to low pressure near 12N114W 1011 mb. It continues to 09N122W to 08N130W and to beyond 07N140W. Scattered moderate to isolated strong convection is seen within 60 nm south of the trough between 116W-118W and within 30 nm of the trough between 106W-110W. Scattered moderate convection is present from 07N to 11N between 137W-140W, and also within 60 nm either side of the trough between 110W-115W and between 125W-136W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong high pressure and associated ridging prevail across the Baja California Peninsula offshore waters. Latest ASCAT satellite data passes show moderate to fresh NW winds offshore Baja California, where 8-12 ft seas prevail and extend to the Colima outer offshore waters. A recent ASCAT satellite data pass indicated fresh to strong NW to N winds from Los Cabos to the Revillagigedo Islands due to a tighter pressure gradient between the ridge and low pressure of 1007 mb that is located near 19N106W. Moderate to fresh NW winds along with slight to moderate seas are over the northern and central Gulf of California while fresh to strong NW winds are over its southern section. Seas there are higher, in the 5-7 ft range. Generally gentle to moderate W to NW winds along with seas of 6-9 ft in long-period NW swell are over the remainder of the Mexican offshore waters. For the forecast, surface ridging will remain in place across the offshore waters of Baja California through mid-week. It will weaken slightly on Mon allowing for the gradient to slacken some. Looking ahead, a new set of long-period NW swell will reach the waters N of Punta Eugenia with seas to peak at around 13 ft from Mon night into Tue evening, at which time the seas from the former swell event would have subsided below 8 ft. Afterward, NW winds along the Baja offshores will diminish to gentle to moderate speeds and continue through Fri night. Looking ahead, the next Gulf of Tehuantepec gap wind gale event is forecast to start Wed evening. Gale force winds and very rough seas are forecast from Wed night through early Sat. An area of low pressure located about 90 nm SW of Jalisco will continue to move slowly east-northeastward, roughly parallel to the southwestern coast of Mexico through Tue bringing increasing shower and thunderstorm activity to the offshore waters of Colima, Jalisco and Nayarit. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh SW winds are ongoing across the Nicaragua, El Salvador and Guatemala offshore waters along with seas of 5-7 ft in mixed SW and NW swell. Gentle to locally moderate winds are across the remainder Central America offshore waters and from Ecuador to the Galapagos Islands. Seas are slight to moderate in mixed SW and NW swell across these waters. Otherwise, scattered to numerous showers and thunderstorms, some heavy, associated with Tropical Depression Sara located over the central Yucatan Peninsula will continue to affect the offshore waters of Guatemala, El Salvador and northern Nicaragua. For the forecast, moderate to fresh SW winds over the offshore waters from Nicaragua to Guatemala will change little through Tue, then diminish slightly Tue night as Tropical Depression Sara moves WNW across the Yucatan Peninsula through Mon morning while it weakens. Gentle to moderate winds along with slight to moderate seas are expected elsewhere through Thu. Looking ahead, a gale gap wind event is forecast to begin in Tehuantepec Wed night. Fresh to strong winds and very rough seas associated with this event are forecast to affect the far western Guatemala offshore waters Thu and Fri. ...REMAINDER OF THE AREA... Please refer to the Special Features sections for details about large swell propagating through the NE forecast waters. A tight pressure gradient related to a strong high pressure center of 1037 mb that is located well NW of the discussion area near 41N151W supports a large area of fresh to strong NE to E winds from 08N to 20N W of 120W, where seas are 8-12 ft, the highest of seas being W of 130W. Mostly fresh NE to E winds are N of 23N. Seas with these winds are , winds are moderate to fresh from the NNE and seas are 6-9 ft in N to NE swell W of 125W, and in NW to N swell E of 125W. Gentle to moderate winds along with seas of 6-8 ft due to long-period NW swell are south of the monsoon trough to 05N, and seas of 5-7 ft are S of 04N. For the forecast, the high pressure will be reinforced by another strong high pressure tonight. As a result, fresh to strong winds will continue to affect most of the waters N of 08N and W of 120W through Mon. Large long-period NW swell will continue to propagate across the forecast region. Seas of 10-12 ft will dominate the west-central waters tonight due to a combination of N to NE swell and wind generated waves. Seas are forecast to drop just below 12 ft late tonight. At that time, seas in excess of 8 ft are forecast to cover much of the waters N of 05N and W of about 100W. $$ Aguirre