000 AXPZ20 KNHC 200356 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Jan 19 2019 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 0000 UTC surface analysis and satellite imagery through 0245 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: The next gap wind event over the Gulf of Tehuantepec is expected to commence tonight as a strong cold front moving across the Gulf of Mexico reaches the Isthmus of Tehuantepec. High pressure building behind the front will provide a very tight gradient over the area, and bring an increase in winds funneling into the Gulf of Tehuantepec. Winds will rapidly increase to gale force tonight, and reach storm force early Sunday. Winds will diminish below storm force Sun night, then below gale force on Mon evening. Seas will peak near 25 ft Sunday during the period of storm force winds. Swell generated from this event will produce a large plume of 12 ft seas that will extend up to 105W by Mon evening. Marine interests transiting the Gulf of Tehuantepec tonight into early next week should be aware of this upcoming gap wind event, and take necessary action to avoid hazardous marine conditions over the affected waters. Please see the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 for further details. Gulf of Papagayo Gale Warning: High pressure will build behind a strong cold front moving across the Gulf of Mexico tonight. This will support strong to near gale force gap winds through the Gulfs of Papagayo and Panama. Winds to gale force are expected in the Gulf of Papagayo Sun night into Mon evening with seas building up to 13 ft by Mon afternoon. Strong winds will pulse across the Gulf of Panama Sun night through Tue night increasing to near gale force early on Mon. Fresh to strong winds will also pulse across the Gulf of Fonseca Sun night through Mon morning. Please see the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from a 1010 mb low pressure located over Colombia near 05N75W to 04N82W to 06N89W. The ITCZ continues from 06N90W to 03N102W to 04N120W to 04N140W. Scattered moderate convection is from 01N to 10N west of 135W. Scattered moderate isolated strong convection is from 07N to 14N between 110W and 117W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please, see special features for more details on the upcoming storm force gap wind event in the Gulf of Tehuantepec starting tonight. A Storm Warning is currently in effect. Elsewhere, moderate north to northwest winds along the offshore waters off Baja California combined with long period NW swell is producing seas of 8 to 12 ft over the waters off Baja California. This swell event will bring dangerous surf and large breaking waves across portions of Baja California through Sun morning. Seas will slowly subside this weekend, falling below 8 ft by Sun afternoon. A new set of NW swell, with seas in the 8 to 11 ft range, will sweep into Baja California Norte offshore waters on Mon morning. This swell will spread across the remainder of the offshore waters of Baja California through Tue night. Gulf of California: High pressure over the Great Basin north of the area is supporting fresh to strong northwest winds across the entire Gulf. The strength, fetch and duration of the winds will support wave heights to 8 ft in the southern Gulf of California tonight. Winds and seas will diminish on Sun afternoon as the high weakens and shifts eastward. Another ridge will build over the Great Basin early on Tue, leading to the return of strong winds along the entire Gulf through the middle of the week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The pressure gradient between high pressure building north of the area and the equatorial trough will maintain strong to near gale force gap winds across Papagayo and Panama through early next week. A Gale Warning has been issued for the Gulf of Papagayo. Please, see special features for more details. REMAINDER OF THE AREA... High pressure of 1025 mb is centered near 29N130W. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting fresh to strong trade winds north of the ITCZ, roughly south of 17N and W of 119W. The ridge will prevail and strenghten over the course of the week, thus maintaining strong winds over the central and western tropical waters. Long period NW swell will continue to dominate this region, with seas 8 ft or more in northwest swell. A cold front will drift SE across the NW corner of the area through Sun afternoon when it will stall while it weakens. High pressure in the wake of the front will bring increasing winds and building seas across the west-central waters, and also over the offshore waters of Baja California, mainly N of Punta Eugenia on Mon. $$ Ramos