000 AXPZ20 KNHC 070925 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sat Mar 7 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: A tight gradient between strong high pressure over eastern Mexico and lower pressures south of Mexico is causing storm force winds over the Gulf of Tehuantepec. Scatterometer data shows a large area of 45-50 kt winds across the region this morning. Gale force winds will persist through Mon morning, diminish slightly through Mon evening, then pulse to gale again Mon night. Peak wave heights will reach about 21 ft today, then gradually subside into early Mon. The wave heights generated by this ongoing high wind event will combine with those originating from the Papagayo region, and propagate far downstream from the individual source regions. 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 05N84W to 04N95W. The ITCZ continues from 04N95W to 09N125W, then resumes from 07N132W to 07N140W. Scattered moderate convection is noted within 60 nm south of the axis between 87W and 90W, and from 05N to 09N between 134W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Special Features section above for details on an ongoing Gulf of Tehunatepec storm wind event. A weak pressure pattern is supporting light to moderate winds across Mexico offshore waters, with the notable exception of the Gulf of Tehuantepec high wind event. Fresh to strong SW winds will affect the northern Gulf of California tonight and Sun as a weakening cold front moves onshore. Large long-period northwest swell will impact the waters west of Baja California Sun through Tue night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: The pressure gradient across Central America is resulting in strong northeast winds offshore the Papagayo region. These winds are expected to reach near gale force Sun night and Mon. Wave heights associated with these winds are expected to be in the range of 8-11 ft. Gulf of Panama: Persistent high pressure north of the area will produce fresh to strong north to northeast winds over the Gulf of Panama for the next several days. Maximum wave heights with these winds are expected to reach 8 to 10 ft. The present Gulf of Tehuantepec gap wind event will bring large west to northwest swell to propagate through the waters west of Guatemala and El Salvador for the next several days. REMAINDER OF THE AREA... A weak ridge prevails across the waters north of 20N. A modest pressure gradient is supporting gentle to moderate northeast trades north of the ITCZ. Long-period swell is producing 7-8 ft seas between 08N and 12N west of 125W. Large NE swell spreading downstream from Tehuantepec and Papagayo will merge together, and encompass most of the waters south of 13N between 90W and 110W by late Sun. A weakening cold front in the far northwest corner of the area is followed by strong north to northeast winds and wave heights of 8-10 ft. This front will weaken to a trough later today as it moves westward north of 25N, then dissipate by early Sun. A stronger cold front will reach the northwest corner of the area on Sun, with strong southwest winds ahead of the front, and strong to near gale force W-NW winds behind it. A large extra- tropical low pressure system will move into the area Sun night, and reach to near 31N130W by early Mon. Strong winds along with wave heights expected to build to the range of 12-18 ft are expected north of 24N and west of 130W on Mon as the cold front pushes into the central waters. There is potential for the winds behind the front to reach gale force Sun night and Mon morning. Please keep abreast of the latest high seas forecast, which will provide wind and wave height details regarding this system. $$ Mundell