000 AXPZ20 KNHC 212205 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Mar 21 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A tight pressure gradient over southeastern Mexico is bringing strong to near near gale force north to northeast winds across the Gulf this afternoon. As the gradient further tightens during the rest of the afternoon, expect for these winds to reach minimal gale force late in the afternoon or in the early evening hours. Seas with these winds are expected to build to around 12 ft. By early Fri afternoon these winds will diminish to just below gale force ,and continue to diminish through early on Sat as the gradient slackens. The seas will subside to less than 8 ft at that time, but prior to doing seas to around 9 ft due to a mixed northeast and northwest swell will be located from 10N to 13N between 95W and 105W by early Fri evening. This area of seas will also subside by early on Sat. The next possible gap wind gale event is expected for early on Mon of next week. 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 specific marine details on this ongoing event. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from a 1010 mb low located over northwest Colombia to the coast at 07N77W and continues to 06N88W, where latest scatterometer data indicated that it transitions to the ITCZ that continues to 05N98W to 03N111W to 03N130W and to beyond the area at 04N140W. Scattered moderate convection is seen within 60 nm south of the trough between 85W-88W, within 30 nm of the ITCZ between 110W-116W, and within 30 nm south of the ITCZ between 97W-101W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for more details about the ongoing Gulf of Tehuantepec gap wind gale event. Gulf of California: Fairly quiet conditions will continue through the upcoming weekend, with seas in the 1-3 ft range. A tight pressure gradient between high pressure ridging, that extends eastward from a high center well west these waters, and a cold front that stretches from northwestern Mexico to across Baja California Sur to the offshore near 22N115W and beyond is resulting in fresh to strong northwest moderate to locally strong winds along and within 120 nm to the west of the Baja California Peninsula with seas to 9 ft in a northwest swell. These winds will increase to mainly strong speeds tonight and continue through early Fri afternoon, before diminishing to mainly fresh winds through the upcoming weekend. Seas will build slightly, to 10 ft, with these winds tonight. By early Sun, northwest to north winds west of Baja California are expected to be mainly in the moderate to fresh range along with seas of 8-11 ft due to a set of new northwest swell that will propagate through the northeast part of the area. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: The winds will pulse to strong speeds beginning late tonight and into the early morning hours assisted by nocturnal drainage off the land. These winds are forecast to continue into the afternoon hours through the upcoming weekend. Guidance indicates that these winds may reach to near gale force early Fri afternoon and again late Fri night and into early on Sat, with seas of 8-10 ft. Gulf of Panama: Fresh northerly winds will pulse to strong, occasionally at night, in the Gulf of Panama through Sat night and into early on Sun afternoon. Peak wave heights are expected to reach 8 or 9 ft with these winds. Between Ecuador and the Galapagos Islands, 4-6 ft seas in mixed swell will build to the range of 5-7 ft during the upcoming weekend with the arrival of both long period southwest and northwest swell. Light to moderate winds and 3-5 ft seas will remain elsewhere through the upcoming weekend. REMAINDER OF THE AREA... Long-period northwest swell associated with a cold front that extends from Baja California Sur southwestward to 19N124W, where it becomes stationary to 20N133W and to near 17N139W is producing seas in the range of 8-10 ft over the waters north of about 05N and east of 128W. This swell will slowly subside through Fri, but the residual of it will be replaced by a new set of northwest swell that will begin to propagate into the far northwest corner of the area tonight in association with a new cold front. Seas associated with this new swell will peak to near 15 ft over the northwest waters on Fri night. A third cold front will arrive over the far northwest part of the area early on Sun, ushering in yet another set of large NW swell to the northwest waters. $$ Aguirre