000 AXPZ20 KNHC 211601 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1251 UTC Tue Feb 21 2017 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning...High pressure is building southward across eastern Mexico in the wake of a frontal system moving slowly east across the Gulf of Mexico. Strong winds generated west of the front are beginning to funnel through the Chivela pass into the Gulf of Tehuantepec. This gap wind event will be brief as winds peak near minimal gale force tonight. Winds will then diminish below gale force early Wednesday morning and below advisory criteria on Wednesday evening. Refer to the High Seas Forecast product under AWIPS/WMO headers MIAHSFEP2/FZPN03 KNHC for additional details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... There is no ITCZ over the forecast waters north of the equator. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above for more on the next Gulf of Tehuantepec gale force gap wind event. Gentle to moderate winds prevail across much of the forecast waters west of Baja as indicated by the latest satellite-derived wind data. Seas continue in the 6-8 ft range in the Baja offshore waters and the waters adjacent to southwest Mexico, 1-3 ft over the Gulf of California, and 3-5 ft over the remainder of the forecast waters. A fresh set of NW swell generated by a cold front west of the area is moving into the Baja California Norte offshore waters. These swell will continue to propagate across the waters off the west coast of the Baja California peninsula and maintain seas in the 6-9 ft range over this area through early Friday. Building high pressure west of Baja California is already generating fresh to strong NW to N winds over the southern Gulf of California and between Cabo San Lucas and Cabo Corrientes. Fresh to strong NW winds are also anticipated along the western Baja coast north of 25N Wednesday night through Thursday night and over the Gulf of California N of 30N on Thursday morning. Winds will subside as the high weakens in response to low pressure approaching from the west. Seas are then expected to subside below 8 ft in this area Friday night through the weekend. Another cold front could bring yet another round of NW swell to Baja waters on Monday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to locally fresh winds this morning will subside by this evening. Gulf of Panama: Moderate winds will become light on Wednesday. Otherwise, winds will be in the light to gentle range over the forecast area. REMAINDER OF THE AREA... High pressure of 1026 mb is centered near 28N123W. A frontal boundary is beginning to stall in the northern waters. The front currently extends from 30N125W to 26N130W to 21N140W. Winds in the vicinity of this front have diminished to 20 kt or less. NW swell generated north of the front continue to propagate SE across the forecast waters as they slowly diminish. Seas west of the front continue to subside. The highest seas near 14 ft are located near 30N133W. The front is beginning to weaken, and is expected to dissipate later today. NW swells continue to dominate the forecast waters, with seas greater than 8 ft covering much of the forecast waters north of 10N and west of 110W. A small area of 20 to 25 kt NE winds is expected to affect the waters from 21N to 23N west of 137W Wednesday and Wednesday night in response to weak surface troughing to the south. Areal coverage of seas greater than 8 ft will start to decrease the second half of the week. By Friday night and Saturday seas greater than 8 ft will be confined to the far NW waters. Yet another set of NW swell will move into the area in response to the arrival of another cold front. $$ cam