000 AXPZ20 KNHC 210919 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0919 UTC Sun Apr 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from 10N84W to 06N90W to 06N96W. The ITCZ continues from 06N96W to 09N115W to 07N125W to 05N135W to beyond 04N140W. Scattered moderate and isolated strong convection is noted from 02N to 06N between 77W and 81W, from 02N to 04N between 93W and 97W, within 60 nm north of the ITCZ between 97W and 100W, and within 120 nm north of the ITCZ between 117W and 128W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad high pressure ridge persists over the offshore waters west of Baja California. The pressure gradient between this ridge and a low pressure trough over Baja California supports moderate NW winds north of Cabo San Lazaro with seas generally 5-7 ft. A weakening cold front or trough will cross the region today with fresh winds developing off Baja California Norte and seas building to 8-9 ft. NW swell will continue impacting the northern waters through Mon night, then seas will subside through midweek. Gulf of California: A 1008 mb low pressure center over the northern Gulf of California is likely supporting fresh to strong SW to W gap winds north of 29.5N. These winds will quickly diminish this morning. Otherwise, light to gentle winds will prevail across the Gulf through Thu. Gulf of Tehuantepec: A recent partial scatterometer pass showed fresh to strong N winds over the Gulf of Tehuantepec. Seas likely reach 10 ft in the Gulf, while a plume of 7-9 ft seas extends well downstream of the region based on 05Z altimeter data. Winds are expected to diminish to gentle speeds by this afternoon. Looking ahead, a weak pressure gradient over the region will result in variable, light to gentle winds across the area Mon through Thu. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE to E winds will pulse across the Gulf of Papagayo and downwind to near 90W through Mon night. Winds will be strongest during the overnight and early morning hours with the assistance of the nocturnal drainage flow. As the pressure gradient weakens through midweek, winds will diminish to moderate to fresh speeds with seas less than 8 ft. Looking ahead, winds and seas will likely continue subsiding through Thu night. Gulf of Panama: Moderate N to NE breezes will prevail across the Gulf of Panama this week with seas generally 3-5 ft in mixed SW swell and NE wind waves. Elsewhere, light to gentle winds will persist across the region with seas of 4-6 ft in S to SW swell. Seas will peak around 7 ft today SW of the Galapagos Islands. REMAINDER OF THE AREA... A high pressure ridge extends SE across the northern waters towards the Revillagigedo Islands. The pressure gradient between this ridge and the ITCZ is supporting fresh trade winds south of 20N west of 125W based on recent ship obs and the latest available scatterometer data. Altimeter passes in this region indicate 8-9 ft seas within the trades south of the ridge. These conditions will generally persist through Mon night as high pressure remains anchored north of the area. The high will weaken Tue through Thu in response to low pressure approaching from the west. This will allow winds and seas to subside through midweek. A set of NW swell associated with a weakening cold front will move into the far northern waters later today. Seas will build to 9 ft NW of Guadalupe Island by tonight and remain 8 ft through Mon night. Elsewhere, S to SW swell will produce seas to 8 ft generally south of the Equator and west of 110W early this week. $$ Reinhart