000 AXPZ20 KNHC 262135 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1848 UTC Wed Dec 26 2018 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 a 1006 mb low pressure over Colombia near 07N75W to 02N81W. The ITCZ continues from 02N81W to 05N110W to 05N120W to beyond 06N140W. Scattered moderate convection is within 90 nm N of ITCZ axis between 105W and 111W...and within 180 nm N of the ITCZ axis between 130W and 135W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Winds are forecast to increase to 20-25 kt across the northern part of the Gulf Thu night through Sun with seas building to 6-8 ft as a frontal trough crosses the region Thu night into Fri. Then, strong high pressure building over the Great Basin will set up a prolonged drainage NW wind event along the entire length of the Gulf of California Fri night through Sun night. Strong NE gap winds could spill out over the offshore forecast waters during this time frame. In addition, the fresh to strong northerly winds are also expected to affect the waters between Los Cabos and Las Tres Marias Islands Sat night and Sun. Gulf of Tehuantepec: A recent scatterometer pass indicates the presence of N winds in the 15-20 kt range in the Tehuantepec region with seas of 5-7 ft based on altimeter data. The residual NE swell generated by the recent strong to gale force N to NE winds will continue to propagate to the SW and W while losing energy. This area will merge with NE to E swell downstream from the Gulf of Papagayo and all of this will continue to subside to less than 8 ft across the waters E of 100W by late tonight. A ridge covering the offshore forecast waters combined with lower pressure over the SW CONUS and northern Mexico is resulting in an area of fresh to locally strong NW to N winds N of Punta Eugenia. Seas in this area are running between 10 and 15 ft in NW swell. The strong NW winds will retreat N of 30N later this afternoon, but they are expected to pulse back across these waters Thu evening through Fri. Seas of 8-10 ft in NW swell are reaching the offshore forecast waters of Baja California Sur, while seas of 8 ft are noted near the Revillagigedo Islands. Seas of 8-11 ft will continue to affect the offshore waters W of Baja California through at least Thu night. Fresh to locally strong winds are observed per scatterometer data within about 90 nm of the coast of Jalisco and Colima. Marine guidance suggests mainly moderate to locally fresh winds in this area through Fri. 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 are expected across the area through Mon. The winds are greatest during the overnight and early morning hours, and could reach near gale force with the assistance of the nocturnal drainage flow. Seas are forecast to build to 8 or 9 ft with the strongest winds. Gulf of Panama: Moderate to fresh northerly winds are expected through Mon with seas generally in the 4 to 6 ft range. Elsewhere: Gentle to moderate NE winds will continue to the north of 08N, while light to gentle south winds are expected S of 08N, with seas in the 4 to 6 ft range throughout. REMAINDER OF THE AREA... A 1032 mb high pressure located near 35N137W extends a ridge SE across the forecast waters to near the Revillagigedo Islands. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ is supporting a large area of fresh to strong NE winds, particularly from 07N to 24N W of 130W, and from 10N to 21N between 118W and 130W. Scatterometer data confirmed the presence of these winds. Seas within this area are ranging in the 8-11 ft range. These marine conditions are forecast to persist over the next couple of days. Long period NW swell will continue to propagate across the forecast waters mainly W of 110W building seas to 8-11 ft. Another set of long period NW swell will begin to propagate across the NW corner of the forecast area on Thu. $$ GR