000 AXPZ20 KNHC 171604 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Nov 17 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 1200 UTC surface analysis and satellite imagery through 1530 UTC. ...SPECIAL FEATURES... Eastern Pacific Swell Event: Long-period NW swell is producing seas of 10-12 ft N of 16N between 108W-124W. This set of swell will slowly decay through this evening, with seas dropping below 12 ft. Another set of long-period NW swell is forecast to enter the offshore and adjacent waters N of Punta Eugenia with seas building to 10-14 ft Mon night, and subside to 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 of 1007 mb near 18N107W SW to 07N133W. The ITCZ begins near 07N133W and continues beyond 07N140W. Scattered moderate to strong convection is from 16N to 23N between 103W and 107W. Scattered moderate convection is elsewhere within 120 nm either side of the monsoon trough and the ITCZ. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong high pressure and associated ridging prevail across the Baja California Peninsula waters. The related gradient supports moderate to fresh NW winds offshore Baja California with 8-12 ft seas extending to the Jalisco outer offshore waters. Locally strong NW winds are likely from Los Cabos to the Jalisco outer offshore waters where a broad area of low pressure is supporting scattered heavy showers and tstms. Moderate to locally fresh NW winds and slight seas are along the Gulf of California, except for moderate seas to 5 ft at the entrance of the Gulf. Moderate to fresh NW to N winds prevail in the Gulf of Tehuantepec region with seas to 5 ft. Gentle to moderate winds and 5-7 ft seas in long-period NW swell dominate the remainder of the SW Mexican offshore waters. For the forecast, a ridge will remain in place across the offshore waters of Baja California through the middle of the 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 14 ft from Mon night into Tue evening, at which time the seas from the former swell event will subside below 8 ft. The fresh winds in the Gulf of Tehuantepec region will diminish to moderate speeds today and change little through the middle of the week. 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 Fri night. An elongated area of low pressure located SW of Jalisco will continue to move eastward or east-northeastward into the early part of the week bringing increasing shower and thunderstorm activity to the offshore waters of Colima and Jalisco. ...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 offshore waters along with seas of 6-7 ft in mixed SW and NW swell. Moderate SW to W winds and moderate seas to 6 ft are across the offshore waters of Guatemala and El Salvador. Elsewhere, winds are gentle to locally moderate from the SW and seas are slight to moderate in mixed SW and NW swell. Scattered heavy showers and thunderstorms associated with Tropical Storm Sara located over Belize continue to affect the offshore waters of Guatemala, El Salvador and northern Nicaragua. For the forecast, the moderate to fresh SW winds over the offshore waters of Nicaragua will weaken slightly tonight as Tropical Storm Sara moves NW towards the Bay of Campeche. Moderate seas are expected over the offshore waters from El Salvador to northern Costa Rica, including the Papagayo region today. Gentle to moderate winds along with moderate seas are expected elsewhere, except between Ecuador and the Galapagos Islands, where winds will remain at mostly light speeds. Scattered to numerous showers and thunderstorms, some possibly heavy, will continue to be quite persistent over the offshore waters of Guatemala, El Salvador, and northern Nicaragua into Mon as the onshore flow of SW winds into the outer circulation of Sara helps to sustain this activity. ...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 1039 mb that is located well NW of the discussion area near 43N159W supports a large area of fresh to strong NE to E winds from 08N to 23N W of 120W where seas are 8-14 ft. N of 23N, winds are moderate to fresh from the NNE and seas are 7-9 ft. Gentle to moderate winds along with seas of 6-8 ft due to long- period NW swell are south of both the monsoon trough and the ITCZ. For the forecast, the high pressure will shift slightly southeastward today, being reinforced by another strong high pressure late today. 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 and long period NW swell will continue to propagate across the forecast region. Seas of 12-14 ft will dominate the west-central waters tonight in a mix of NW swell and wind waves. Seas are expected to subside below 12 ft on Mon. 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. $$ Ramos