000 AXPZ20 KNHC 220927 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 925 UTC Sat Dec 22 2018 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 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 0800 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A ridge across the SW Gulf of Mexico and the eastern slopes of the Sierra Madre mountains continues to support a gale force gap wind event across the Gulf of Tehunatepec. The Gale force winds will diminish on Sat as the high pressure north of the area shifts eastward. Gale conditions are expected again across the Tehunatepec area Sun night through Mon. Please refer to the latest high seas forecast issued under AWIPS/WMO headers HSFEP2/FZNPN03 for more specific marine details. Gulf of Papagayo Gale Warning: High pressure building in behind a stationary front that extends from Jamaica to central Costa Rica is producing a tight pressure gradient over northern Central America which is resulting in minimal gale force winds over the Gulf of Papagayo. Peak seas of 9 to 12 ft are expected in and downstream of the Gulf during this gale event. These winds are forecast to diminish to below gale force briefly early this afternoon, then increase again to minimal gale force tonight. Fresh to strong winds are then expected across the Gulf of Papagayo Sun afternoon through at least midweek next week. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the coast of Colombia near 06N77W to 04N96W. The ITCZ continues from 04N96W to 07N107W, then resumes W of a surface trough near 07N113W to beyond 08N140W. Scattered moderate convection is from 06N to 15N between 105W and 113W, and from 05N to 10N between 132W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features Section above for information on the ongoing strong gale force gap wind over the Gulf of Tehuantepec. Long period NW swell continues to propagate across the offshore forecast waters with seas of 7 to 9 ft covering much of the area. Seas, everywhere outside the Gulf of Tehunatepec, will subside below 8 ft through today. The next round of large swell is forecast to reach the offshore waters of Baja California Norte by early on Mon, and the remainder of the Baja California Peninsula offshore waters by early on Tue. Wave guidance is indicating that seas will build to 12 to 16 ft N of Punta Eugenia on Tue. By that time, fresh to strong NW winds are also forecast to affect the offshore waters N of 26N. These winds will increase to strong to near gale-force by Tue evening before diminishing early Wed. Gulf of California: Winds are light and variable across the area with a trough meandering along the west coast of mainland Mexico. These conditions will persist through this weekend. Minimal gale force winds are possible across the northern Gulf of California on Tue as strong surface low pressure crosses the SW United States. Seas are forecast to build to 6 to 9 ft with these winds. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please the Special Features Section for more on the gale force gap wind event over the Gulf of Papagayo. Strong north winds will prevail over the Gulf of Panama through Sun night, with seas building to 8 ft by early Sun. Elsewhere, gentle to moderate winds will prevail, with seas in the 4 to 7 ft range. REMAINDER OF THE AREA... The pressure gradient between high pressure centered near 30N143W and lower pressure present near the ITCZ is producing fresh to strong northeast trades from 06N to 16N west of 135W along with seas ranging from 9 to 11 ft in combined northwest swell and northeast wind waves. This area of trades and associated seas will expand north and east through early next week. Seas of 8 ft or greater in NW swell extend across all the open east Pacific discussion waters W of 105N. The seas will diminish below 8 ft across the area by tonight except under the stronger trades, and in an area of mixed swell south of about 15N between 90W and 110W, as the lingering NW swell mixes with shorter period northeast swell from the Tehuantepec and Papagayo gap wind events. A new set of NW swell will increase seas N of 16N and W of 120W Sun night through early next week. $$ Latto