000 AXPZ20 KNHC 220240 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0240 UTC Sat Feb 22 2020 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 0240 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: The pressure gradient between high pressure across the eastern slopes of the Sierra Madre Mountains in Mexico and the equatorial trough in the eastern north Pacific is supporting storm force across the Tehuantepec region. Seas are expected to build to near 22 ft tonight. The area of high pressure N of the area will weaken slightly tonight. This will loosen the pressure gradient, and winds will diminish below storm force. The area of high pressure will gradually continue to weaken through the weekend, loosening the pressure gradient and bring a gradual decrease in winds. By Sun afternoon, winds are forecast to diminish below gale force. Swell generated by this gap wind event combined with long period SW swell will produce a large area of 8 ft seas or greater covering the waters from 02N to 12N between 90W and 110W by Sun morning. Marine interest transiting across or in the vicinity of the Gulf of Tehuantepec this weekend should be aware of this gap wind event and take the necessary action to avoid hazardous marine conditions over the affected waters. 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 08N82W to 03N97W. The ITCZ continues from 03N97W to 06N140W. Scattered moderate isolated strong convection was noted from 03N to 07N between 83W and 87W. Scattered moderate convection was noted from 05N to 07N between 113W and 116W. Scattered moderate isolated strong convection was noted from 06N to 09N between 127W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Storm Warning is in effect for the Gulf of Tehuantepec. Please read the Special Features section for more details. Looking ahead, the next strong gap wind event, possibly to storm force, is possible the middle to end of next week. Elsewhere, a weak pressure pattern is supporting light to gentle NW-N winds, and seas of 3 to 5 ft off the coast of Baja California. A cold front approaching the area will slowly dissipate as it moves across Baja California Norte and the northern Gulf of California through Sat. Winds will become moderate to locally fresh across the offshore waters W of Baja California as the gradient tightens in the wake of the front. Winds could reach 25 kt offshore of Cabo Corrientes by the end of the weekend into early next week. Seas are forecast to gradually build to 6-9 ft in NW swell this weekend. In addition, winds will briefly freshen ahead and behind the front over the northern Gulf of California on Sat. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... NW swell generated by the storm force gap wind event in the Gulf of Tehuantepec will propagate into the waters offshore Guatemala and El Salvador through Sun. Seas will reach up to 14-16 ft near 11N95W. Gulf of Papagayo: Fresh to strong winds will continue to pulse during the overnight hours across the Papagayo region through the weekend. Winds will diminish early next week as the pressure gradient weakens. Maximum seas will reach between 8-10 ft during period of peak winds. Gulf of Panama: Fresh to occasionally strong north winds will pulse across the Gulf of Panama through the weekend, diminishing early next week. Maximum seas will build to 6-8 ft at times with these winds. Elsewhere, gentle to moderate winds and seas of 4-6 ft will prevail into early next week. Looking ahead, an unseasonably strong southerly jet is forecast to develop along the lee of the Andes over eastern Ecuador and SW Colombia late Sat night. During this time, environmental conditions appear favorable for heavy rainfall and localized flooding to develop due to strong topographical forcing. REMAINDER OF THE AREA... A weakening cold front is analyzed from 30N122W to 27N121W to 21N133W. Fresh northerly winds prevails behind the front. The front has ushered in a set of NW swell into the NW waters, with seas in the 8-10 ft range. The front will continue to weaken as it shifts eastward toward Baja California Norte and the northern Gulf of California. High pressure in the wake of the front will support fresh to strong trade winds N of the ITCZ and W of 125W through the upcoming weekend. Seas are forecast to build to 8 to 12 ft within the area of the trades. Fresh NE-E swells generated by gap wind events in the Gulf of Tehuantepec and Gulf of Papagayo will propagate far from its source region into an area from the equator to 13N between 90W and 110W this weekend, gradually decaying by early next week. $$ AL