000 AXPZ20 KNHC 151519 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1500 UTC Fri Mar 15 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front will continue moving across the western Gulf of Mexico and into the Bay of Campeche early this evening. Strong high pressure building southward behind the front will support strengthening northerly winds through the Chivela Pass tonight. Winds across the Gulf of Tehuantepec will increase to minimal gale force late tonight into Sat, then peak around 40 kt on Sat evening. Northerly winds will continue to pulse to gale force mainly at night through Tue night. Seas will quickly build with the first pulse of gale force north winds, reaching 14 ft by Saturday night. The resultant north to northeast swell will propagate downstream, well away from the Gulf of Tehuantepec to near 100W through Sun. 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 trough extends from 07N84W to 06N94W. The ITCZ continues from 06N94W to 03.5N110W to 03.5N130W to beyond 05N140W. Scattered moderate isolated strong convection is within 90 nm of the ITCZ between 118W and 125W. Similar convection is also noted within 60 nm south of the ITCZ between 96W and 99W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Strong high pressure across the Great Basin, with the associated pressure gradient supports strong northwest winds across the central Gulf of California, while fresh northwesterly winds prevail elsewhere across the Gulf. An earlier scatterometer pass showed 25 to 30 kt winds between 25N and 29N. Seas to 9 ft over the Gulf this morning will subside to less than 8 ft by early Sat morning as winds diminish to 20 kt or less. Gentle to moderate NW to N winds likely prevail off Baja California this morning. Earlier altimeter data showed seas to 11 ft in NW swell in this region. Seas will gradually subside by early Sat morning as gentle to moderate winds continue through early next week. Gulf of Tehuantepec: A gale warning has been issued for the Gulf of Tehuantepec. Please see special features section for details. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fairly strong high pressure ridging north of the western Caribbean and Central America will continue to support fresh to strong northeast winds pulsing across the Gulf of Papagayo through the upcoming weekend and into early next week, increasing to 25-30 kt Sat night through Mon night. Seas will build to 10 ft by Sat night with the increasing winds through the Gulf. Gulf of Panama: Moderate to fresh northerly winds across the Gulf of Panama will continue through Sat, then increase to 20-25 kt Sat night into Sun morning. Wind speeds will diminish into early next week. Elsewhere, gentle to moderate northeast to east winds along with 5-7 ft seas will continue across the waters east of 90W through Tue night. REMAINDER OF THE AREA... A broad ridge extends SE from a 1028 mb high near 38N129W to just beyond the Revillagigedo Islands. The pressure gradient between the ridge and the ITCZ supports an area of fresh trade winds, mainly south of 20N and west of 115W. Earlier altimeter data showed 8 to 11 ft seas in mixed NE wind waves and NW swell. Trades will slightly diminish over the next couple days as the ridge gradually weakens. Long-period northwest swell persists over much of the region west of 100W this morning. This swell will gradually decay through the weekend. A strong cold front will approach the NW corner of the forecast region by Sun. Strong to near gale force winds are expected ahead of the front on Sun, increasing to minimal gale force Sun night. Seas will build to 17 ft by Mon night in long period NW swell. This swell will continue to propagate across the northern waters west of 120W through Tue night as winds diminish to moderate to fresh speeds ahead of the front. $$ Reinhart