000 AXPZ20 KNHC 181518 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sat Dec 18 2021 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 1500 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from southern Costa Rica near 09N83W to 08N95W to 1011 low pressure located near 10N107W. The ITCZ continues from 10N107W to 08N120W, then from 08N128W to 10N138W. Scattered moderate convection is noted from 10N to 14N between 100W and 111W, and from 07N to 12N between 115W and 128W. Numerous moderate to isolated strong convection is observed from 08N to 15N W of 134W. This convective activity is associated with a surface trough located just W of area. OFFSHORE WATERS WITHIN 250 NM OF MEXICO High pressure of 1027 mb located near 33N130W extends a ridge across the offshore waters on Baja California producing mainly gentle to moderate NW to N winds. Gentle to moderate northerly winds are also noted between Las Maria Islands and Los Cabos, including the entrance to the Gulf of California while light to gentle winds are elsewhere over the open waters off Mexico. Fresh to locally strong winds are blowing across the north and central Gulf of California. Seas are in the 6-8 ft range N of Cabo San Lazaro, and 4-6 ft elsewhere over the open waters off Mexico. Seas of 3-5 ft prevail in the Gulf of California, except 4-6 ft in the northern part of the Gulf where the strongest winds can be found. For the forecast, NW swell with seas in the 6-8 ft range will continue to dominate the offshore forecast waters of Baja California today before it begins to decay into Sunday. Fresh to strong winds in the north and central parts of the Gulf of California will persist through tonight. A new gap wind event is expected in the Tehuantepec region beginning on Sun night, with gale conditions possible on Tue and Tue night. Seas are forecast to build to 10-13 ft with the strongest winds. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR Fresh to strong NE winds are observed in the Gulf of Papagayo region tonight. Light to gentle winds are noted elsewhere north of the monsoon trough. Gentle to moderate S to SW winds are also noted south of the monsoon trough. Seas ranged between 3 to 5 ft in mixed swell. For the forecast, NE to E winds will pulse to fresh to strong in the Papagayo region through the next several days and into next week, particularly during the overnight and early morning hours. each day. Gentle to moderate winds will prevail elsewhere. No significant swell events are forecast through early next week. REMAINDER OF THE AREA... Surface high pressure centered near 33N130W dominates the waters north of the ITCZ with a pretty tight pressure gradient. As a result, pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ is supporting an area of fresh to locally strong trade winds from 13N to 20N W of 125W. Gentle to moderate winds prevail elsewhere. NW to N swell continues to propagate mainly across the waters west of 110W, producing seas of 8-11 ft. Seas of 5-7 ft are noted elsewhere. For the forecast, the area of fresh to locally strong trade winds will persist across the west-central waters today. The large NW to N swell event affecting mainly the waters W of 110W will gradually decay through the remainder of the weekend. The next cold front is forecast to move southeast of 30N140W on Sun with fresh to locally strong winds on either side of the front. The front will slowly progress east-southeast through early next week. The front will bring another NW swell event, building seas to 8-12 ft. $$ GR