608 AXPZ20 KNHC 120915 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Dec 12 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 0600 UTC surface analysis and satellite imagery through 0855 UTC. ...SPECIAL FEATURES... Tehuantepec Gale Warning: A strong high pressure system over the SE United States continues to sustain gale to strong gale-force winds in the Gulf of Tehuantepec. This was confirmed by a recent scatterometer satellite pass. Strong winds associated with this gap wind event are occurring as far south as 11N. Seas are currently near 18 ft. The gale-force winds will diminish Thu, with strong winds continuing through the end of the week. Seas will drop below 12 ft by Thu. Please read the latest High Seas Forecast and the Offshore Waters Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and www.nhc.noaa.gov/marine/offshores.php for details on the special feature. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Panama near 08N82W to 06N100W. The ITCZ stretches from 06N100W to 07N120W to beyond 06N140W. Scattered moderate to isolated strong convection is present from 06N to 13N and between 115W and 129W. Similar convection is noted from 06N to 09N and west of 136W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the SPECIAL FEATURES section for details on a Gale Warning for the Tehuantepec region. The pressure gradient between the subtropical ridge near 32N136W and lower pressures over southern California sustain moderate to locally fresh NW winds in the offshore waters well west of Baja California Norte. Seas in these waters are 4-7 ft. Moderate or weaker winds and slight to moderate seas prevail in the remainder of the Mexican offshore waters, including the Gulf of California. For the forecast outside of the Gulf of Tehuantepec, a surge of fresh winds will bring NW swell with seas to 8 ft to the Baja California Norte waters N of Punta Eugenia today. Meanwhile, strong winds are possible across the Gulf of California Fri into Sat. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Rough seas continue to affect the offshore waters of Guatemala and El Salvador due to the swell from the Gulf of Tehuantepec gap wind event. The 8 ft seas extend as far east as 90W. Meanwhile, fresh to strong NE-E gap winds are prevalent across the Gulf of Papagayo region, including the coast of southern Nicaragua. These winds extend westward to about 90W. Seas in these waters are 5-8 ft. Elsewhere, moderate or weaker winds and 3-6 ft seas prevail in combined mixed swell. For the forecast, the rough seas affecting the Guatemala and El Salvador offshore waters will continue today into Wed, subsiding Wed night into Thu. Fresh to strong NE-E winds are forecast across the Papagayo region through early Fri. Seas peaking near 9-10 ft today into Wed, subsiding below 8 ft by Thu. Gentle to moderate breezes are expected elsewhere. ...REMAINDER OF THE AREA... A 1024 mb high pressure system is located near 32N136W and extends southeastward to the Revillagigedo Islands. The pressure gradient between the aforementioned ridge and lower pressures in the deep tropics support fresh to strong easterly trade winds, mainly north of the ITCZ to 22N and west of 115W. A recent scatterometer pass indicate that strong to near gale-force winds are occurring in the areas of strong convection in the ITCZ. Seas in these waters are 8-12 ft as shown by the latest altimeter satellite pass. Fresh to occasionally strong NE-E winds associated with the gap wind event ongoing in the Gulf of Tehuantepec extend into the eastern waters of the basin, mainly north of 07N and between 95W and 107W. Seas in these waters are 8-12 ft. Meanwhile, south of the ITCZ, moderate to locally fresh SE-E winds prevail with seas 6-8 ft. In the remainder of the basin, moderate or weaker winds and moderate seas are prevalent. For the forecast, the broad ridge to the north will weaken as it drifts eastward through midweek, allowing the trade winds and seas to diminish. Fresh to strong NE winds associated with Tehuantepec gap winds will continue reaching the high seas over the next several days. Winds and seas will eventually subside from this event by Thu into Thu night. A large, long-period swell should reach the NW corner of the waters by Wed night as a cold front approaches the region and stalls. A reinforcing cold front will move across this region by Thu into Fri, with low pressure forming along the boundary. This low could potentially produce gale-force winds late this week and into the weekend with very rough seas. $$ Delgado