000 AXPZ20 KNHC 080241 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0240 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 05N77W to 03N81W, then continues from 07N89W to 04N103W. The ITCZ begins near 04N103W and continues to 06N112W to 04N130W to beyond 04N140W. Scattered moderate and isolated strong convection is noted within 210 nm north of the ITCZ between 122W and 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad high pressure ridge extends southeastward across the Baja California offshore waters to near the Revillagigedo Islands. The pressure gradient between this ridge and lower pressure over inland Mexico is likely producing fresh northerly winds off the Baja California coast based on earlier scatterometer data and recent ship observations. Large, long period NW swell is producing 8-11 ft seas over the offshore waters north of Cabo San Lozaro. This swell will continue producing dangerous surf conditions along the Baja California coast through Mon night. The swell will gradually reach the southern Mexico offshore waters south of Cabo Corrientes by Tue with 8-9 ft peak seas. 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 may reach as high as 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 Lozaro through Fri. Gulf of California: Moderate to fresh NW winds are occurring over the central Gulf of California this evening with gentle to moderate breezes elsewhere. 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. Seas will build to 7 ft in the Gulf by Wed, then subside late in the week as the pressure gradient relaxes. Gulf of Tehuantepec: Gentle 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. The ridge is supporting fresh to locally strong NE to E trade winds across much of the area. Earlier scatterometer data showed a broad area of 20-25 kt winds south of the ridge from 09N to 17N. 19Z altimeter data indicated a region of 9-11 ft seas north of the ITCZ roughly between 120W and 125W. At 00Z, the highest seas to 12 ft were analyzed near 17N132W based on an assessment of the available wave guidance. A set of large, long period NW swell continues to propagate across the region. 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 02S near 100W. A cold front will move SE into the far NW portion of the forecast area later tonight and 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. $$ Reinhart