000 AXPZ20 KNHC 042157 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2115 UTC Mon Mar 4 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Open East Pacific Waters Gale Warning: A dissipating cold front extends along 30N135W to 25N139W. Behind that, a new cold front has entered the area at 30N138W to 27N140W. Fresh to strong S to SW winds are ahead of the dissipating front. Behind the cold front, winds are W strong breeze to near gales. Seas to 12 ft are already affecting our NW corner at 30N140W. The cold front will continue to move into the area tonight ushering in strong to near gale force winds N of 27N, with frequent gusts to gale force likely. A new set of large NW swell of 16 ft will also accompany the front, forecast to reach a position from 30N128W to 21N136W by early Tue morning, and from 30N122W to 22N130W by early Wed morning. Winds will diminish below gale force by Tue afternoon, then to fresh levels Tue night, while the swell train will continue to propagate SE across the forecast region, with seas of 8 ft or greater dominating the waters W of a line from 30N124W to 20N130W to 13N140W by Wed morning. Then, seas will gradually subside to less than 8 ft by late Thu. Gulf of Tehuantepec Gale Warning: High pressure building in E of the Sierra Madre Oriental in Mexico behind a strong cold front will cause the next gap wind event in the Gulf of Tehuantepec beginning tonight. Strong winds will begin to funnel through the Chivela Pass tonight, reaching gale force by Tue morning and continuing as a gale through Thu morning. It is anticipated that winds will peak at 40-45 kt and seas reach almost 20 feet early Wed morning. This Tehuantepecer should end Fri afternoon. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details about these gale warnings. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough axis extends from 07N82W to 06N88W. The Intertropical Convergence Zone axis continues from 06N88W to 01N110W to 03N125W to 05N140W. Scattered moderate to isolated strong convection is from 03N to 06N between 126W and 131W. Similar convection is also noted near 06N133W. As it is normal for this time of the year, a second and pretty active ITCZ is analyzed S of the Equator. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: A Gale Warning is in effect for the Gulf of Tehuantepec. Please read the Special Features section for details. On Thu, a weakening cold front will reach Baja California Norte with minimal impacts. Conditions should remain quiescent W of Baja California for the next several days. No large long-period swell is anticipated to affect the region. Gulf of California: Developing low pressure over the U.S. Great Basin will support nocturnal pulsing of fresh to strong SW to W in the northern Gulf of California Thu night and Fri night. Generally benign marine conditions are expected elsewhere across the Gulf through at least Sat night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Fonseca, Papagayo, and Panama: A moderate pressure gradient in the western Caribbean combined with nocturnal drainage flow will produce enhanced winds in the Gulfs of Papagayo and Panama each evening through at least Sat night. The forcing is strongest Tue through Thu nights and also causes strong breeze conditions in the Gulf of Fonseca those evenings. Winds should peak around near gale in the Gulf of Papagayo Wed and Thu morning with peak seas of 10-12 ft. Winds should peak around strong breeze in the Gulf of Panama Wed, Thu, and Fri mornings with peak seas of around 8 ft. No large long-period swell are expected to impact the area for the next several days. REMAINDER OF THE AREA... Marine conditions are beginning to deteriorate N of 26N W of 130W as a low pressure system and associated frontal boundaries affect this region. Please see the Special Features Section for more details on a developing gale warning. Elsewhere, long-period NW swell mixing with tradewind flow is maintaining an area of 7 to 9 ft seas from 06N to 12N W of 127W. These seas will gradually subside to less than 8 ft by early Tue. Later in the week, another combination of mixed NW swell and wind waves are expected to support seas of 7 to 9 ft roughly across the same area. $$ Landsea