000 AXPZ20 KNHC 082136 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2135 UTC Fri Mar 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the Costa Rica coast near 09.5N85W to 06N90W. From there, the ITCZ extends to 02N120W to beyond 04N140W. Scattered moderate convection is occurring within 60 nm north of the ITCZ axis between 95W and 105W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak cold front is drifting eastward across the waters west of Baja California Norte and across the northern Gulf of California. A few showers are possible just ahead of the front. Farther south, fresh to strong northerly gap winds persist through the Gulf of Tehuantepec, but these will diminish 10 kt or less this evening as the pressure gradient continues to relax across the Gulf of Mexico. Associated seas are 5 to 7 ft. Elsewhere over Mexican offshore waters, latest scatterometer and altimeter satellite data indicate gentle to moderate winds across the region with 4 to 6 ft seas. For the forecast, the cold front over Baja California and the northern Gulf of California will dissipate through tonight. A stronger cold front will late Sun through early next week, with strong SW gap winds impacting the northern Gulf of California ahead of the front on Sun. Enhanced NW winds and large long- period NW swell will follow the front in waters west of the whole Baja California peninsula reaching to the Revillagigedo Islands. Hazardous surf conditions are possible early next week along the coast of Baja California as a result. Elsewhere, moderate breezes and seas will persist over the offshore waters of Mexico through mid week. No new Gulf of Tehuantepec gap wind event is expected for the next several days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A scatterometer satellite pass from 15 UTC indicated fresh to strong NE gap winds through the Gulf of Papagayo to well west of the area. The winds have diminished from last night and yesterday when near gale to gale force winds were active in this region due to a relatively tight pressure gradient over northern Central America. Associated downstream seas are 7 to 10 ft in this plume, mostly due to residual shorter period swell from the stronger overnight winds. Fresh to strong gap winds are likely still active through the western Gulf of Panama off the Azuero peninsula. While the pressure gradient over northern Central America has relaxed a little due to high pressure farther north shifting eastward, conditions are still in place to support persistent strong to near gale force gaps for some time across the Gulf of Papagayo and off the coast of Nicaragua. These gap winds will be strongest in late night to early morning hours and will continue with little change through at mid week. Fresh to strong N to NE gap winds also will pulse through the Gulf of Panama as well through mid week, mainly at night. REMAINDER OF THE AREA... Ridging is building west to east along roughly 27N in the wake of a weakening frontal boundary shifting east of the region into Baja California. The ridge is support development of fresh trade wind flow farther south. A recent scatterometer pass indicated a large area of 20 kt trade winds from mainly 10N to 15N west of 135W. Associated seas in the area of fresh winds are estimated to be 8 to 9 ft, with an added component of longer period NW swell. A second, somewhat stronger cold front is approaching the region from the northwest. This will move into the waters of the discussion area tonight, reaching from southern California to 22N132W by Sat afternoon, then will move east of the area through Sun. Strong northerly winds will follow the front by Sat night, along with reinforcing NW swell of up to 15 ft across the waters north of 20N into early next week. This longer period NW swell will decay somewhat as it moves southeast through early next week, but swell in excess of 8 ft will cover the entire region west of 110W by mid week. In addition, a ridge will again build west to east over the waters north of 20N in the wake of the second front, supporting fresh to strong NE trade winds across the deep tropics south of 15N and west of 120W through mid week. $$ Christensen