000 AXPZ20 KNHC 281004 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Mar 28 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 0600 UTC surface analysis and satellite imagery through 0930 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Gale force winds up to 40 kt will persist through late Thu morning as surface high pressure builds southward across the western Gulf of Mexico. Peak seas will be in the range of 12-16 ft reaching well downstream of the Gulf to about 10N100W. 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 more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the coast of Colombia near 05N77W to 06N88W. The ITCZ continues from 06N88W to 05N93W to 0N112W to 03N130W beyond 04N140W. Scattered moderate to isolated strong rainshowers are within 60 nm to the north of the surface trough and ITCZ between 85W and 97W, and within 120 nm to the north of the ITCZ between 97W and 103W. Scattered moderate to isolated strong rainshowers are within 60 nm to the south of the ITCZ between 121W and 128W, and within 30 nm to the north of the ITCZ between 120W and 125W. Isolated moderate to locally strong rainshowers are within 480 nm to the north of the ITCZ from 130W westward, and within 120 nm to the south of the ITCZ between 130W and 134W. A second ITCZ passes through 03.4S110W to 03.4S113W beyond 03.4S114W. Widely scattered to scattered moderate and isolated strong rainshowers are within 90 nm to the north of the ITCZ between 110W and 118W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Please refer to the Special Features section for more information about the current Warning for gale- force winds. The gale-force wind conditions are expected to diminish this afternoon, as the ridge that spans the Gulf of Mexico slides eastward, and return flow is established N of the area. Fresh to strong winds will continue across the Gulf of Tehuantepec area until Friday morning. The next gap wind event is forecast to start on Monday morning. Gale-force wind conditions are forecast to develop again on Monday night. Gulf of California: Light to gentle winds and seas less than 4 ft will prevail through early Fri. NNW winds in the range of 15- 20 kt will become established early on Friday, and continuing through Monday morning, as high pressure briefly builds into the Great Basin. A surface high pressure, that is to the west of Baja California, supports gentle to moderate NW winds across the adjacent offshore waters. The pressure gradient will tighten between the ridge, which will strengthen as it moves NE, and low pressure developing in the southern CONUS and Mexico by Thursday. This will lead to the development of fresh to strong NW to N winds off Baja California N of 25N starting on Thursday evening, and continuing through Saturday morning. The sea heights will build to 10 feet by Thursday night in the waters north of Punta Eugenia, and to 9 feet elsewhere in the offshore waters. Moderate to fresh NW winds and seas to 8 feet in mixed swell will dominate the offshore waters from Saturday afternoon through Sunday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong to near gale force NE to E winds will continue pulsing in the Gulf of Papagayo through late Friday morning. The comparatively fastest wind speeds each day will occur during the late night and early morning hours, as nocturnal drainage flow enhances wind speeds. The sea heights will peak to 11 feet during this period and extend downstream to 08N92W. The wind speeds generally will range from moderate to fresh during the remainder weekend. Gulf of Panama: Fresh to strong N to NE winds in the Gulf of Panama will persist through Thursday morning, as surface high pressure builds into the Caribbean Sea. Moderate to fresh wind speeds will dominate the Gulf waters from Thursday afternoon until Sunday. The sea heights will reach 8 feet during the gap wind event, being supported by NE wind waves and cross- equatorial SW swell. Satellite analysis shows light smoke impacting the offshore waters from Guatemala to El Salvador and Nicaragua. The sea heights will grow from less than 8 feet to 9 feet from this afternoon until Friday afternoon. The sea heights will subside from Friday afternoon until Saturday night. REMAINDER OF THE AREA... A surface trough is along 28N126W to 25N130W to 22N134W. NW swell associated with the front is supporting an area of 8-11 ft seas in the NW forecast waters roughly north of 25N between 125W and 136W. Another cold front is expected to stall just NW of the forecast area on Fri, which will introduce another set of long period NW swell that will propagate SE across the high seas beginning Thu. Moderate to fresh NE to E trade winds prevail from 03N to 14N W of 110W. Seas in this region are generally in the 8-9 ft range. The trade winds will strengthen to fresh to strong W of 120W by Thu morning and persist through Sat morning as strong high pressure builds north of 30N. A combination of longer period NW and SW swell is maintaining an area of 8-9 ft seas generally south of 15N between 88W and 120W. Similar wave heights will persist into early Sat being supported by the gap winds events in the Gulf of Tehuantepec and Gulf of Papagayo. $$ mt