000 AXPZ20 KNHC 110228 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Mar 11 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 0000 UTC surface analysis and satellite imagery through 0215 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: North to northeast gale force winds continue across the Gulf of Tehuantepec due to a fairly tight pressure gradient resulting from the combination between high pressure north of area and lower pressure present in the eastern Pacific. These ongoing gale force winds will continue through early Wed afternoon, at which time they are forecast to diminish to strong to near gale force speeds as the gradient slackens some. Current wave heights in the range of 9-12 ft with these gale force winds are forecast to subside to 8-10 ft by late Wed night as these winds diminish to strong speeds. By Thu morning, these winds are forecast to diminish to mainly fresh speeds and to light to moderate speeds Thu afternoon, with wave heights lowering to less than 8 ft. For more information 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...Updated A trough axis extends from 08N84W to 03N93W, where afternoon scatterometer data indicated the ITCZ axis begins and continues to 03N104W to 02N112W to 04N117W to 03N125W to 05N131W. It is briefly interrupted by a trough that extends from 13N128W to 03N133W. The ITCZ resumes at 07N132W and to beyond 07N140W. Scattered moderate convection is within 30 nm of trough axis between 89W and 92W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on a gap wind event in the Tehuantepec region. Gentle to moderate southerly winds are offshore Baja California Norte head of a weakening cold front that is approaching from the west. Fresh northwest to north winds over the southern Gulf of California and southward to Cabo Corrientes will increase tonight, then diminish to mainly fresh winds Wed and increase to strong speeds Wed night and diminish on Thu. Southwest winds will increase to fresh to strong over the northern Gulf of California ahead of another cold front Thu night and Fri. Farther south, long-period southerly swell will dominate the Mexican offshore waters south of 20N through late week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: A tight pressure gradient due to the combination between high pressure over the western Caribbean Sea that extends across the northern part of the Central America with lower pressure over the remainder of Central America and the eastern Pacific is bringing strong northeast winds to the Gulf of Papagayo region. This synoptic pattern set-up will continue through Fri allowing for these winds to change little. The gradient is expected to weaken on Thu, and this will cause these winds to diminish to moderate to fresh speeds at that time. Wave heights in the range of 8-10 ft are west of the Gulf region from 07N to 11N between 89W and 93W. These wave heights subside during the overnight hours, however similar wave heights will build closer to the Gulf on Wed, then subside to less than 8 ft Wed afternoon. Gulf of Panama: Presently, fresh to strong north to northeast winds across and downstream of the Gulf are supported by a tight gradient between high pressure over the Caribbean Sea and lower pressure from Colombia southwestward to Central America and the eastern Pacific tightens a little. However, these winds will be short-lived as low pressure over northwestern Colombia will weaken during the overnight hours allowing the gradient to slacken just enough to allow for these winds to diminish mainly moderate speeds by early Wed. Wave heights to 8 ft from the early strong north winds across these waters are well downstream from the Gulf from 01N to 05N between 81W and 82W will subside to less than 8 ft late tonight. Elsewhere, mixed northeast and southwest swell is resulting in a large area of high seas, with wave heights peaking up to 10 ft, are evident over much of the waters off the coast of Central America. These wave heights are expected to slowly subside during the next couple of days. REMAINDER OF THE AREA... Strong to near gale-force northwest to north along with wave heights of 10-14 ft follow a cold front that extends from near 32N118W to 23N120W and to near 16N140W. A 1011 mb low associated to this front is near 30N126W with a trailing trough to 27N132W. Another trough is behind the front from 30N119W to near 23N124W. Areas of rain along with scattered showers and isolated thunderstorms are occurring ahead of this front north of 20N and eastward to over much of Baja California. As this front weakens Wed into Thu, winds and seas will diminish. Looking ahead, high pressure building north of the area in the wake of the front will support fresh trade winds and wave heights to 8 to 9 ft over the deep tropics from 08N to 15N west of 130W Fri into Sat. Farther east, a large area of 8-10 ft wave heights persists from roughly 01N to 13N between 93W and 120W from a mix of southerly swell and shorter period northeast to east swell originating from gap wind events in the Gulfs of Tehuantepec and Papagayo. This will diminish below 8 ft for the most part Wed into Thu. $$ Aguirre