000 AXPZ20 KNHC 082032 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2130 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Gulf of California Gale Warning: A cold front is expected to move southward across the northern Gulf of California Tue night. Model guidance has trended stronger with the post-frontal northerly winds as strong high pressure builds into the region. A brief period of gale force winds appears increasingly likely over the far northern Gulf late Tue night, and so a gale warning will be issued. Seas will build to 8-9 ft north of 30N by early Wed morning, then subside as wind speeds diminish over the northern Gulf on Wed. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 10N86W to 04N100W. The ITCZ begins near 04N100W and continues to 06N115W to 04N130W to beyond 02N140W. Scattered moderate convection is noted from 05N to 07N between 89W and 92W and also from 06N to 08N between 128W and 131W. ...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. The pressure gradient between this ridge and lower pressure over inland Mexico is likely producing moderate northerly breezes across the Baja California waters. Large, long period NW swell moving through the regional waters has reached the Revillagigedo Islands and is producing 8-10 ft seas over the offshore waters north of Cabo San Lazaro, and 6-9 ft seas as far southward as Cabo San Lucas. This swell will continue producing dangerous surf conditions along the coast of Baja California tonight. The swell will gradually spread across the southern offshore waters as far south as Puerto Angel through Wed with 6-8 ft seas expected. 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 this evening. The next gap wind event in the Gulf of Tehuantepec is expected late tonight through early Wed 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: Light to gentle winds will prevail 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 tonight 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... 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 S, cross equatorial SW swell is producing a small area of 8 ft seas south of 01S near 100W. A cold front has just moved SE into the far NW portion of the forecast area. High pressure at 1025 mb near 30N130W extends a ridge SE to near 17N120W. Mainly moderate to locally fresh trades cover the waters ahead of the front and N of the ITCZ under the ridge. Strong high pressure building in the wake of this front will support a tightening pressure gradient across the 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. Recent altimeter data indicated seas of 8-11 ft in this region. $$ Reinhart