817 AXPZ20 KNHC 072209 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Dec 7 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: The pressure gradient between high pressure north of the area and lower pressures in the deep tropics is producing strong to gale-force northerly winds in the Gulf of Tehuantepec. These gale winds are forecast to continue through tonight then become fresh to strong Sun morning. These winds will diminish below strong force on Mon. Rough seas are expected to continue through the weekend. Please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at the website- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and https://www.nhc.noaa.gov/marine/offshores_eastpac.php for details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A monsoon trough extends from the southeastern coast of Panama to 06N96W. An ITCZ continues from 06N96W to 09N117W, then from 09N121W to beyond 07N140W. Scattered moderate convection is seen from 07N to 14N between 96W and 127W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section above a Gale Warning in the Gulf of Tehuantepec region. A broad ridge dominates the waters north of 20N, anchored by a 1029 mb high pressure off southern California. This pattern maintains gentle to moderate winds and 3 to 6 ft seas across the Mexican offshore waters, other than the Gulf of Tehuantepec. For the forecast, gale-force gap winds and rough seas across the Gulf of Tehuantepec will continue through tonight before gradually diminishing through Sun, as high pressure north of the area weakens and shifts eastward. Winds near Cabo Corrientes will reach fresh to strong Sun night. Gentle to moderate winds and moderate seas will persist elsewhere into early next week. Looking ahead, fresh to strong winds and building seas will follow a cold front moving down the length of the Gulf of California late Mon night through Wed. Farther south, strong gales are possible over the Gulf of Tehuantepec by Wed following a cold front moving through southern Mexico. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A strong ridge over the central United States is maintaining fresh to locally strong NE to E winds in the Gulf of Papagayo and extending downstream to 90W, seas are at 5 to 7 ft. Elsewhere, moderate or weaker winds and moderate seas are prevalent. For the forecast, NE swell generated from a gap wind event in the Gulf of Tehuantepec will linger at the far offshore waters of Guatemala through tonight. A strong surface ridge north of the Caribbean will support pulses of fresh to strong gap winds across the Gulf of Papagayo through Sun night. Gentle to moderate winds and moderate seas primarily in SW swell will persist elsewhere. ...REMAINDER OF THE AREA... A 1029 mb high pressure system positioned north of the area supports moderate to fresh northeasterly trade winds south of 20N to the ITCZ. Seas over these waters are 7 to 9 ft, with the highest seas occurring in the trade wind zone of the deep tropics west of 125W. North of 20N and west of 120W, gentle to moderate N to E winds with 6 to 8 ft seas are present. Elsewhere, moderate or weaker winds and moderate seas prevail. For the forecast, high pressure will maintain moderate to fresh NE to E trade winds over the waters from 10N to 20N west of 120W through Mon. Meanwhile, NW swell will move into the region, reinforcing and maintaining 7 to 10 ft wave heights not only in the trade wind zone, but farther north to the west of 130W. Looking ahead, the trade winds and associated seas will increase west of 130W into mid-week as high pressure builds north of the region. Farther east, moderate to fresh NE to E winds originating from the gap wind event across Tehuantepec are reaching as far west as 110W. A trough along the monsoon trough near 120W will drift farther southwest of the Revillagigedo Islands, enhancing the winds and supporting seas to 8 ft near the trough axis through Monday. This will be joined by fresh easterly winds from the Papagayo gap wind event to support an elongated area of seas to 8 ft from 08N to 12N to the north of the ITCZ before subsiding late Mon. These winds and seas diminish through mid week. $$ Chan