000 AXPZ20 KNHC 290935 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Jan 29 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 0600 UTC surface analysis and satellite imagery through 0930 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: The latest scatterometer overnight depicted storm force winds across the Gulf of Tehuantepec, with gale force winds occurring downwind to about 13N. A building ridge across the eastern slopes of the Sierra Madre Mountains in Mexico is supporting this gap wind event. Seas are peaking around 12-21 ft. Storm force winds will end early this morning, with gale force winds prevailing through Wed night. Meanwhile, large seas generated from this gap wind event will continue spreading well away from the Tehuantepec area, with seas 8 ft or greater reaching as far west as 110W by Tue. Conditions will begin to improve by Thu. Marine interests transiting across or in the Gulf of Tehuantepec should be aware of this gap wind event, and take the necessary action to avoid this hazardous marine conditions over the affected waters. Of note: The monthly distribution of Tehuantepec events shows that the largest number of gale force events occurs in December. Storm-force events occur most often in January. Gulf of Papagayo Gale Warning: High pressure is building across the eastern Gulf of Mexico and the NW Caribbean in the wake of a cold front within the Gulf of Mexico. This will support fresh to strong NE to E winds in the Gulf of Papagayo and downwind to beyond 90W. Frequent gusts to gale force are expected, especially at night through at least Wed night. Rough seas will build to near 12 ft with the strongest winds today through Tue night. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information on this event. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... An equatorial trough extends from the coast of Colombia near 06N77W to 04N93W. The ITCZ extends from 04N93W to 06N120W to beyond 04N140W. Scattered moderate to isolated strong convection is noted from 04N to 16N between 106W and 125W. This convective activity in near the base of an upper-level trough. Fresh to locally strong easterly winds are noted per scatterometer data in this area. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Storm Warning remains in effect for the Gulf of Tehuantepec. Please see the Special Features section above for more details. A surface ridge extends from 1020 mb high pressure centered near 29N125W southward into the tropical eastern Pacific. This pattern is supporting light to gentle winds across the Baja California offshore waters, as depicted by the latest scatterometer data. Seas are 4 to 7 ft in NW swell. In the Gulf of California, scatterometer showed moderate N to NW winds across the Gulf. Seas are to 3 ft. Outside of the Tehuantepec region, light to gentle breezes are observed elsewhere over Mexican offshore waters with seas of 4 to 6 ft primarily in NW swell. For the forecast, a ridge will remain in control of the weather pattern across the offshore waters of Baja California through at least mid-week. In the southern Gulf of California, the ridge combined with lower pressure over Mexico will support moderate to fresh NW winds and seas of 3 to 5 ft through Tue. Storm- force winds across the Gulf of Tehuantepec will drop to gale force this morning. Gale conditions will persist through Wed night. Seas will be very rough to high across this region through Tue, and will drop below 8 ft by Thu. Meanwhile, a cold front will reach the waters N of Punta Eugenia by Wed night into Thu. This front will bring fresh to strong winds and very rough seas Thu through at least Fri. Winds are also expected to increase to fresh to strong speeds across most of the Gulf Thu through Fri night in the Gulf of California. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A Gale Warning is in effect for the Gulf of Papagayo. Please see the Special Features section above for more information. Fresh to strong NE to E gap winds prevail across the Gulf of Papagayo region, extending offshore to near 08N91W. Winds are likely gusting to gale force in this area. Seas range 8 to 11 ft. Fresh to strong N winds are noted across the Gulf of Panama N of 06N, with seas of 4 to 7 ft. Light to gentle breezes are noted elsewhere, with 4 to 5 ft seas primarily in SW swell. For the forecast, as high pressure builds across the eastern Gulf of Mexico and NW Caribbean, fresh to strong NE to E winds with frequent gusts to gale force are expected in the Gulf of Papagayo through at least Wed night. Seas will build in this area to 8 to 11 ft. Persistent fresh to strong speeds will pulse in the Gulf of Panama at night through Wed night under the influence of the same high pressure. Seas are forecast to build to 8 ft. Northwesterly swell associated with a significant gap wind event in the Tehuantepec region combined with seas generated in the Papagayo area will affect the offshore waters of Guatemala and El Salvador beyond 90 nm through Wed. Seas are expected to build to 10 to 14 ft through tonight. Otherwise, gentle breezes and moderate S to SW swell will persist elsewhere. ...REMAINDER OF THE AREA... As previously mentioned, a 1020 mb high pressure centered near 29N125W extends a ridge southward into the tropical eastern Pacific. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting moderate to fresh trade winds north of the ITCZ to about 17N and west of 105W. Seas range 6 to 8 ft in this area, primarily in merging NW swell and NE to E wind waves. Meanwhile, an area of fresh to strong winds is in the vicinity of the ITCZ with seas 8 to 9 ft from 06N to 13N between 110W and 115W. This area is also seeing scattered moderate to isolated strong convection. Mainly light to gentle winds dominate the waters N of 20N and W of 110W, with seas ranging 6 to 7 ft. In the NW corner of the forecast region, fresh to strong southerly winds are noted ahead of a frontal boundary located W of the forecast area, mostly N of 26N and W of 135W. Seas are 8 to 12 ft with NW swell in this region. Gentle to moderate breezes and 6-7 ft combined seas persist elsewhere. For the forecast, fresh to strong S to SW winds, and seas of 9 to 13 ft will persist over the NW corner of the forecast region through tonight ahead of a frontal system. A cold front will enter the forecast waters on Tue and continue moving eastward across the waters through the rest of the week. Winds will continue to be fresh to strong from Tue through Thu. Winds could be near gale force on Tue ahead of the front. Large and long period NW swell, with seas in the 12 to 17 ft range, is expected in the wake of the front. An area of fresh to strong easterly winds is expected N of the ITCZ roughly between 110W and 120W through Tue night as the base of an upper- level trough is forecast to persist in this region. Seas could build to 8 to 9 ft near the higher winds. $$ AReinhart