000 AXPZ20 KNHC 310910 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 910 UTC Sun Mar 31 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 0845 UTC. ...SPECIAL FEATURES... ...GULF OF TEHUANTEPEC GALE WARNING... A short duration gale-force gap wind event is expected across the Gulf of Tehuantepec late Sun night into early Mon morning as a high pressure ridge builds southward over eastern Mexico behind a cold front. Seas will quickly build to 8-11 ft early on Mon while a plume of 8 ft seas will propagate downstream of the Gulf later in the day. 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 the coast of Colombia near 07N78W to 06N90W. The ITCZ continues from 06N90W to 03N105W to 04N120W to 02N135W to beyond 03N140W. A second ITCZ extends from 03.4S94W to 02S100W to 03.4S110W. Scattered moderate and isolated strong convection is noted from 01.5S to 03.4S between 102W and 107W. Elsewhere, scattered moderate convection is occurring from 03.5N to 06.5N between 85W and 88W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface ridge extends from 30N126W to near the Islas Revillagigedo. The pressure gradient between this ridge and lower pressure over Mexico is producing moderate to fresh NW to N winds across the offshore waters off Baja California roughly north of 23N based on recent scatterometer data. Seas are generally 8-9 ft across this region in NW swell. Winds and seas will decrease through early next week as the ridge weakens. Gulf of California: Locally fresh NW winds are likely occurring over the central Gulf of California with gentle to moderate winds prevailing elsewhere across the Gulf. Seas peak in the 3-5 ft range over the southern Gulf with 2-4 ft further north. Looking ahead, expect diminishing winds with seas 3 ft or less early next week as the pressure gradient weakens considerably. Gulf of Tehuantepec: See the Special Features section above for more details on the gale warning in effect. Gales will diminish by Mon afternoon with gap winds pulsing to strong to near gale force speeds through Tue night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Recent scatterometer data depicted moderate E winds across the Gulf of Papagayo. Fresh to strong winds will pulse across the Papagayo region during the overnight and early morning hours through early next week. Gulf of Panama: Gentle to moderate N to NE winds will prevail across the Gulf and downstream to 05N through Tue night. High pressure will build north of the area on Wed as winds strengthen to fresh speeds across the Gulf through Thu. Elsewhere, light to gentle winds will prevail through midweek. REMAINDER OF THE AREA... A cold front NW of the area will slowly shift eastward and move into the far NW waters early Mon morning. Winds behind the front will continue to generate long period NW swell that will produce 8-9 ft seas over the far NW waters. The front will gradually weaken as it moves across the far NW portion of the area through early next week. The pressure gradient between high pressure north of 30N and lower pressure near the ITCZ is producing moderate to locally fresh trade winds south of about 20N and west of 120W based on the latest scatterometer data. A 0230 UTC altimeter pass showed seas to 11 ft over this region in mixed swell. Areal coverage of 8 ft seas will gradually decrease over this area during the next few days as winds diminish in response to high pressure weakening over the northern waters. $$ Reinhart