000 AXPZ20 KNHC 211551 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 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 1530 UTC surface analysis and satellite imagery through 1200 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough axis extends from 10N84W to 06N90W to 06N96W. The ITCZ continues from 06N96W to 09N113W to 04N130W to beyond 04N140W. Scattered moderate and isolated strong convection is noted from 02N to 06N between 77W and 82W, within 180 nm north of the ITCZ between 121W-127W and also within 120 nm north of the ITCZ between 111W-115W. ...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 the middle part of the upcoming week. Gulf of California: The combination between a 1010 mb low over the northern Gulf of California and strong high pressure west of the Baja California Peninsula is maintaining fresh to strong southwest to west gap winds north of 29.5N. These winds will quickly diminish this morning, then start up again late tonight before diminishing to moderate to fresh winds during Mon morning and to generally light winds Mon afternoon. Otherwise, light to gentle winds will prevail across the Gulf well into next week. 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 northeast to east 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. The pressure gradient will slacken Tue through Thu allowing for winds to diminish to moderate to fresh speeds and further to light to gentle winds beginning late Wed. Gulf of Panama: Moderate north to northeast winds will continue across the Gulf of Panama this upcoming week with seas generally 3-5 ft in mixed southwest and northeast wind waves. Elsewhere, light to gentle winds will persist across the region with seas of 4-6 ft in south to southwest swell. Waveheights peaking to around 7 ft today southwest of the Galapagos Islands will subside slightly tonight into Mon. REMAINDER OF THE AREA... A high pressure ridge extends southeastward 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 long-period northwest 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, south to southwest swell will produce seas to 8 ft generally south of the Equator and west of 110W early this upcoming week. $$ Aguirre