000 AXPZ20 KNHC 012121 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Mar 1 2018 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... A Gale Warning is in effect for the Gulf of Tehuantepec. Strong northerly winds in the 20-25 kt range will begin to surge across the Gulf of Tehuantepec by late tonight. The northerly winds will gradually increase to minimal gale force on early Fri afternoon, and these winds will persist through early Sat morning. Then, fresh to strong N-NE winds of 25-30 kt are expected through Sun. Please refer to the East Pacific High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough is analyzed from 06N89W to 02N100W. The ITCZ continues from 02N100W to 04N120W to 05N140W. Isolated moderate convection is noted near the eastern end of the trough axis from 04N-07N between 88W-91W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Pacific waters W of the Baja Peninsula: A ridge dominates the offshore forecast waters producing moderate to fresh northerly winds and seas of 6-8 ft. Expect the seas to briefly subside to less than 8 ft late tonight into early Fri morning. Another cold front will reach 30N120W on Fri night, bringing another round of NW swell. Seas are forecast to build to 8 to 11 ft N of 25N W of 115W on Sat, with seas of 7 to 9 ft W of Baja California Peninsula on Sun. Seas will subside to less than 8 ft late Mon. Gulf of California: Latest scatterometer data indicated moderate to fresh NW-N winds S of 26N spreading S of the Gulf to near 22N and E of 109W. Winds are forecast to increase again to 15-20 kt across the northern Gulf on Sat night, ahead of a another cold front crossing the area. Then, winds will shift to NW 20 to 25 kt late Sat night behind the front. NW winds of 20-25 kt will spread across the central and southern waters on Sun night and Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Volcanic Ash Advisory...The Fuego Volcano inland over Southern Guatemala near at 14.5N 90.9W continues to produce volcanic ash emissions. The volcanic ash plume is difficult to observe due to the cloud cover. This is forecast to continue through the next 12 hours based on the latest advisory issued today at 1916 UTC. Gulf of Papagayo: Fresh to locally strong NE winds will continue to pulse through and downstream of the Gulf of Papagayo through the upcoming weekend, with seas building to 8 ft. Gulf of Panama: Fresh to locally strong winds are expected through the forecast period, particularly at night. Outside the above mentioned Gulfs, expect gentle to moderate NE-E winds N of 06N, and E-SE winds S of 06N. REMAINDER OF THE AREA... High pressure located well NW of the forecast area extends a ridge across the north waters, roughly covering N of 15N W of 110W. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ continues to support fresh to strong trades across the waters from 08N-20N W of 120W. The most recent scatterometer data confirmed the presence of these wind speeds. Altimeter data indicate seas of 8 to 13 ft within the area of the trade winds. The aerial extent of the trades will slightly diminish over the next 24 hours as a new cold front reaches the northern forecast waters. Seas are forecast to subside to 8-11 ft on Fri, and 8-10 ft on Sat. A cold front, currently N of area along 33N/34N is forecast to reach the northern forecast waters tonight followed by another set of long period NW swell. This swell event will propagate S across the waters N of 20N W of 116W late on Sat. $$ GR