000 AXPZ20 KNHC 080941 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Apr 8 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 0800 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 10N85W TO 06N98W. The ITCZ begins near 06N104W TO 06N121W TO 02.5N133W to beyond 03N140W. Widely scattered moderate isolated strong convection is noted within 90 nm NW and 240 nm SE of the trough between 82W and 98W, and within 90 nm of the ITCZ between 135W and 140W. Scattered moderate to strong convection is from 03N to 10N between 117W and 132W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad high pressure ridge extends southeastward across the Baja California offshore waters to just beyond the Revillagigedo Islands near 19N107W. The pressure gradient between this ridge and lower pressure over inland Mexico is producing fresh northerly winds across the Baja California waters based on overnight scatterometer data and recent ship observations. Large, long period NW swell moving through the regional waters has reach the Revillagigedo Islands in recent hours, and is producing 8-11 ft seas over the offshore waters north of Cabo San Lazaro, and 6-9 ft seas southward to 20N. This swell will continue producing dangerous surf conditions along the Baja California coast and through Mon night. The swell will gradually build across the coasts of central Mexico from Las Tres Marias to Puerto Angel this afternoon through Wed, with peak seas of 6- 8 ft. Looking ahead, winds are expected to strengthen to 20-25 kt over the offshore waters north of Cabo San Lazaro Tue through Wed as strong high pressure builds north of the region. Seas will build to 12-15 ft over the waters north of Punta Eugenia on Tue night in mixed swell. Wind speeds will gradually diminish by late week but remain fresh north of Cabo San Lazaro through Fri. Gulf of California: Moderate to fresh NW winds continue over the central and south portions of the Gulf of California this morning with gentle to moderate breezes north portions. Winds will diminish to gentle speeds by Tue as the pressure gradient weakens. Fresh to strong NW winds will develop across the northern and central Gulf late Tue night through Wed night as strong high pressure builds into the region, and a cold frontal system sweeps across the region. Winds 25-30 kt may briefly spill into far north portions of the Gulf Tue evening and night and then spread southward through Wed. Seas will build to 8 ft in the north Gulf briefly Tue night, and build to 6-8 ft across central portions Wed afternoon through night, then subside late in the week as the pressure gradient relaxes. Gulf of Tehuantepec: Gentle S to SW winds are expected across the Tehuantepec region through Mon. The next gap wind event in the Gulf of Tehuantepec is expected late Mon night through Tue as strong N winds funnel through the Chivela Pass and across the Gulf. These gap winds are expected to remain well below gale force. Gentle to moderate breezes return mid to late week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to fresh NE to E winds are expected across the Gulf of Papagayo region through Mon. Then, light to gentle winds will prevail Mon night through Fri night. Gulf of Panama: Light to gentle breezes will prevail across the Gulf of Panama region this week. Seas will build to 5-7 ft by midweek as long period SW swell propagates into the area. Elsewhere, light to gentle winds will persist through the week. Wave heights between Ecuador and the Galapagos Islands will build to 5-7 ft beginning on Mon night as cross equatorial, long period SW swell moves into the region. SW swell will continue impacting the southern waters through the end of the week. REMAINDER OF THE AREA... A broad high pressure ridge persists across the northern waters, centered on a 1026 mb surface high near 31N129W. The ridge is supporting fresh to locally strong NE to E tradewinds across much of the area between the ITCZ and 23N and to the W of 115W. Overnight scatterometer data showed an area of 20-25 kt winds south of the ridge from 05N to 12N between 130W and 135W. Recent altimeter data indicated seas of 9-11 ft in this region and generally 8-10 ft elsewhere across the tradewind belt. Large, long period NW swell continues to propagate through the regional waters this morning, and has moved into the deep tropical Pacific waters. The swell will cover most of the waters west of 105W by Tue with seas ranging from 8-11 ft. Further south, cross equatorial SW swell is producing a small area of 8 ft seas south of 02.5S near 100W. A cold front has just moved SE into the far NW portion of the forecast area and will extend from 30N131W to 26N140W by Mon night. Strong high pressure building in the wake of this front will support a tightening pressure gradient across the northern waters Tue through Thu night. This will result in a large area of fresh to strong N to NE winds across much of the region north of 18N through midweek. Northerly winds could approach 30 kt just beyond the Baja California Norte offshore waters Tue night. Seas will build to 12-15 ft across this region Tue night and persist into Wed night as NW swell mixes with S swell and NE wind waves. Expect wind speeds to diminish Fri and Fri night as high pressure weakens and moves westward, finally allowing the pressure gradient to relax. $$ Stripling