000 AXPZ20 KNHC 162205 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Jan 16 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwest Colombia near 09N78W to low pressure of 1012 mb near 05N100W and to 05N110W. Latest scatterometer data indicates that the ITCZ extends from 09N122W to 07N130W to beyond 08N140W. Scattered moderate to isolated strong convection is within 120 nm north of the trough between 97W-100W. Scattered moderate convection is within 60 nm either side of the ITCZ between 124W-128W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to strong SW winds are over the northern Gulf of California ahead of a cold front that is just moving onshore Baja California Norte. High pressure dominates the offshore waters of Baja California Sur, with an associated ridge extending to southern Gulf of California. The pressure gradient between the ridge and lower pressures inland Mexico currently supports moderate to locally fresh NW winds roughly across the offshore waters between Cabo Corrientes and Manzanillo. In the Gulf of Tehuantepec region, light and variable winds continue there. Long-period NW swell is propagating across most of the offshore waters of Mexico, with seas generally in the 8-11 ft range N of Acapulco, except for higher seas of 10-13 ft N of 29N. For the forecast, fresh to strong winds will persist in the northern Gulf of California through early Tue afternoon as another cold front moves across the area. Seas will build to 8 ft. Light to gentle winds will prevail in the Tehuantepec region through the week along with 4-6 ft seas. Long-period NW swell will continue to propagate across the offshore waters of Baja California. Another set of large NW swell has recently begun to propagate through the offshore waters of Baja California Norte. Resultant seas are building, and are expected to reach the range of 10-14 ft N of Punta Eugenia by early this evening. This swell event will bring seas of 9-12 ft to the waters N of Cabo San Lazaro on Tue. These seas will slowly subside through late Thu as the swell decays. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong winds are in the Gulf of Papagayo and downwind to near 88W with seas of 8-9 ft. Fresh NE winds are in the Gulf of Panama and near the Azuero peninsula, with seas of 5-7 ft. Gentle to moderate winds are noted elsewhere. Outside of the Papagayo region, long-period W-NW swell spreading across the area has raised seas to the range of 6-8 ft over the offshore waters from northern Costa Rica to Guatemala per latest altimeter data pass over these water. Elsewhere seas of 5-7 ft are present, except 4-6 ft between Ecuador and the Galapagos Islands. For the forecast, fresh to strong winds are expected in the Gulf of Papagayo through early Tue, then mainly fresh winds will prevail through Fri. Fresh to strong winds are expected to pulse in the Gulf of Panama, and east of the Azuero Peninsula through this morning. Seas from northern Costa Rica to Guatemala offshore waters will subside by Tue. Winds will be moderate or weaker elsewhere through at least the next several days. REMAINDER OF THE AREA... A cold front over the northern waters extends from an occluded front that is over southern California, south-southwestward to 30N117W to 25N130W and to 26N140W. Fresh to strong NW-N winds and rough to very rough seas follow the front. A recent altimeter data pass revealed seas of 14 ft near 30N122W. Elsewhere, a surface ridge dominates the waters N of 10N west of about 110W. Latest available ASCAT data passes generally depict light to gentle winds under the influence of the ridge, except for moderate to fresh NE winds confined to the southern periphery of the ridge where a tighter pressure gradient exists between the ITCZ and 15N. Long-period NW swell dominates most of the forecast region with seas of 8-11 ft across most of the waters west of 90W. For the forecast, large and long-period NW swell will continue to propagate across most of the forecast waters through at least Wed, as another set entering the forecast region behind the aforementioned cold front. The cold front will move across Baja California Norte through this evening, reach from near 30N113W to 22N130W and weakening to 23N140W by late tonight, then begin to weaken from near 25N112W to 23N125W and to 22N140W by early Tue and reach from near 23N110W to 20N125W and to 19N140W as a dissipating frontal boundary by early Wed afternoon. The rough to very rough in the wake of the front will gradually subside through late Wed. Fresh NW winds following in behind the front are forecast to spread across the waters W of Baja California Norte through Tue, then across the waters W of the northern part of Baja California Sur through early before diminishing to moderate speeds. Seas will gradually subside across the discussion area by late Thu. Weak low pressure over the eastern part of the area is producing scattered moderate to isolated strong convection from 05N to 08N between 97W-100W. An ASCAT data pass near the low suggested fresh NE-E winds associated to the convection. The low pressure is forecast by model guidance to shift W-NW through late Wed, but remain rather weak. $$ Aguirre