000 AXPZ20 KNHC 031549 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Wed Jan 3 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 1550 UTC. ...SPECIAL FEATURES... Large Area of High Seas: NW swell generated by a large low pressure system just offshore of the Pacific Northwest coasts of the U.S. and Canada continue to enter the local Pacific waters N of 24N and W of 120W this morning. This is occurring just behind a cold front moving across the region, and that currently extends from 30N121W to 25N140W. Seas across this area are presently 8 to 14 ft in building NW swell. This swell will continue to propagate southeastward and into the Baja California Norte waters this afternoon, with and behind the cold front that will reach Baja Norte late this afternoon. The front is expected to continue moving SE and gradually dissipate, as it reaches Cabo San Lucas and adjacent offshore waters Thu evening. NW swell associated with this system will build to 12 to 17 ft across the Baja Norte offshore waters by Thu morning, accompanied by strong N-NW winds behind the front. On Thu and Thu night, seas of 12 ft and greater will eventually cover a large area that will extend from 23N to beyond 30N, between the Baja California coastal waters and 130W. Winds and seas will begin to subside late Thu night through Fri, falling below 12 ft by Fri afternoon. Meanwhile, strong high pressure behind the cold front will settle just N of the area near 31N138W today through Thu. The pressure gradient between this high and the ITCZ will continue to produce a large area of fresh to strong trade winds south of 24N and W of 122W this afternoon through Fri, to produce large and steep seas in E-NE trade wind swell. This trade wind swell will merge with incoming NW swell to produce a large area of combined seas of 12 ft and greater beginning this afternoon through Thu night, from 09N to 22N and west of 130W. Another pulse of large NW swell will then enter the far NW waters late Thu night to expand the area of seas 12 ft and greater to beyond 30N. Peak seas in the trade wind zone are expected to reach 13-14 ft Thu and Thu night. Seas W of 130W will eventually begin to subside significantly on Sun. Please refer to the High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and https://www.nhc.noaa.gov/marine/offshores_eastpac.php for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N73.5W to 09N83W to 1012 mb low pressure near 04N104W. The ITCZ extends from 04.5N108W to 08N126W to beyond 06N140W. Widely scattered moderate convection is noted from 01.5N to 04.5N E of 89W. Scattered moderate isolated strong convection is noted from 02N to 07.5N between 93W and 108W, and from 05N to 10N between 125W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A modest ridge extends southeastward into the area tonight, ahead of an approaching cold front that has reached 125W. The associated pressure gradient is supporting gentle to moderate N winds across the Baja California offshore waters, and N to NE winds from Cabo Corrientes to the waters beyond the Revillagigedo Islands. Seas across the Baja offshores are in the 6 to 8 ft range in NW swell, except 6 to 7 ft S of Cabo San Lazaro to 17N. Gentle NW winds are occurring inside the northern Gulf of California with seas to 2 ft, while moderate to locally fresh NW winds prevail elsewhere across the Gulf waters. Seas of 4 to 5 ft extend from central portions to the entrance of the Gulf. To the southeast, gentle to moderate NW to N winds prevail across the Mexican offshore waters between Colima and Puerto Angel, where seas are 5 to 7 ft. In the Gulf of Tehuantepec, recent satellite derived scatterometer winds showed fresh NW winds to the north of 15N, and gentle winds elsewhere across the area. Seas across Tehuantepec have subsided to 4 to 5 ft. Much further offshore of Tehuantepec, seas are 7 to 8 ft in mixed N and W swell to the S of 12.5N. For the forecast, NW swell offshore of Baja California will subside modestly into the afternoon hours. A cold front will reach the offshore waters of Baja California Norte by mid-day, reach Punta Eugenia by Wed evening, then gradually dissipate offshore of Cabo San Lucas and Baja Sur by Thu evening. Fresh to strong NW to N winds will follow in behind the front to the north of Cabo San Lazaro and persist through Thu evening before diminishing. Fresh to strong W gap winds will briefly occur in the northern and central Gulf of California Wed evening and night with the front. High seas in mixed NW swell will follow in behind this front, affecting the offshore waters of Baja California late Wed afternoon through Fri. Seas across Baja Norte will peak at 12 to 17 ft late Wed night and Thu, with seas to 12 ft reaching as far S as 23N Thu evening. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE gap winds persist across the Papagayo region, and extend offshore to near 90W, with seas 7 to 9 ft. Moderate to locally fresh N to NNE winds continue in the Gulf of Panama N of 05.5N with seas to 6 ft. Light to gentle winds are ongoing across the Costa Rica, El Salvador and Guatemala offshore waters where seas are in the 5-7 ft range in W to NW swell. Between the coast of Ecuador and the Galapagos Islands, winds are gentle to moderate from the south, with seas 6 to 7 ft in W to NW swell. For the forecast, a ridge north of the area will support fresh to locally strong NE gap winds over the Papagayo region through today, with seas of 7 to 9 ft persisting in NW to W swell. Moderate to fresh NE to E winds will continue to pulse at night there through Sat as the ridge N of the area weakens. Moderate northerly winds will persist across the Gulf of Panama through Sat. Otherwise, a weak pressure gradient will result in light to gentle winds across the rest of the area through the end of this week. ...REMAINDER OF THE AREA... A cold front extends from 30N125W to 26N140W. Gentle to moderate N to NE winds were depicted north of the front by recent scatterometer winds, where seas are 8 to 13 ft in building NW swell. Seas of 7 to 10 ft prevail ahead of this front extending E to the Baja California offshore waters. Recent scatterometer winds also showed fresh to strong NE to E trades ongoing from 07N to 24N and west of 125W. Moderate to fresh N to NE winds are elsewhere N of 10N and W of 120W. Farther east, an area of 8 to 9 ft seas in NW swell is to the NW of the Galapagos Islands. For the forecast, the cold front will move SE and reach from near 30N118W to 25N130W midday today, and from the central Gulf of California to Cabo San Lazaro to 23N130W by Thu morning. Large NW swell filling in behind this front will build seas to 12 to 16 ft across the waters north of 24N tonight through Thu. Fresh to strong trade winds between the ITCZ and 23N, and west of 120W, will increase to strong and expand in areal coverage through Fri, leading to seas of 11 to 15 ft across that area. See the special features section above for more information. $$ Ramos