000 AXPZ20 KNHC 191538 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Tue Mar 19 2024 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 1538 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: High pressure is building behind a cold front moving through the Gulf of Mexico. This pattern, along with local drainage flow effects, will support gap winds to minimal gale force to pulse across the Gulf of Tehuantepec into early this morning, and again this evening into Wed morning. Expect sustained winds to briefly reach 35 kt during this times, with seas building as high as 10 ft downstream across the Gulf of Tehuantepec through early Wed. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 09N79W to 04N94W to 03N108W. The ITCZ continues from 03N108W to 03N127W to 03N140W. Scattered moderate convection is noted from 02N to 08N between 81W and 93W, and between 100W and 110W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information about a gale warning for the Gulf of Tehuantepec. A surface ridge extends from north of the area off the U.S. west coast, to off Baja California to coast of Michoacan. This pattern is supporting fresh to strong NW to N winds funneling off Cabo Corrientes, but maintaining gentle to moderate breezes elsewhere across the offshore waters of Mexico. Moderate combined seas prevail everywhere, including most of the Gulf of California. For the forecast, as described in the Special Features section, near-gale to gale force gap are ongoing over the Gulf of Tehuantepec, associated with a cold front moving into southern Mexico. Winds will pulse to gale force again tonight. These gap winds and associated rough seas will diminish across the Gulf of Tehuantepec by Wed afternoon. Farther north, moderate to fresh NW winds may pulse from the central Gulf of California to Cabo Corrientes this afternoon and tonight as the high pressure builds west of the region and low pressure deepens over central Mexico. Gentle to moderate winds and seas 4 to 6 ft will prevail from mid to late week across the region. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR Moderate to fresh NE gap winds are present across the Gulf of Papagayo. This gap wind event is due to a combination of local drainage effects and a relatively tight gradient related to high pressure north of the area. Seas within this winds are 4 to 6 ft. Elsewhere seas 3 to 5 ft seas prevail except, seas to 8 ft persist close to the south of the offshore waters around the Galapagos in the southern swell. For the forecast, high pressure north of the area will continue to support pulses of fresh northeast to east winds in the Papagayo region through mid week with locally rough seas. Light to gentle winds and moderate seas will continue elsewhere through the forecast period. ...REMAINDER OF THE AREA... A 1013 mb broad area of low pressure is located near 22N137W. This low is associated with a broad, negatively tilted mid to upper level trough reaching from northwest of the region, where related divergent flow aloft continue to support clusters of showers and thunderstorms southeast of the center of the low pressure, from 22N to 24N between 128W and 130W. Earlier scatterometer data depicted localized near- gale force to gale winds in this area of convection. Broad surface ridging is in place elsewhere north of 20N, supporting mostly gentle breezes across the region, except for moderate trade wind flow over tropical waters from 06N to 16N. NW swell of 6 to 7 ft covers most of the region west of 105W, with seas to 9 ft in the area of moderate trade winds, and farther south of the equator where a component of SE swell is adding to the mix. Combined seas of 5 to 7 ft in mixed NW and S swell are evident east of 105W. For the forecast, low pressure west of the area along the surface trough will continue to move eastward today and weaken, with winds moderate to fresh along 140W and north of 23N. The low may linger through tonight before weakening and opening to a trough. Shorter period wind waves created by moderate to fresh swell from 05N to 15N west of 110W will mix with the longer period NW swell propagating across the region to maintain 8 to 9 ft combined seas in the area of moderate to fresh trade winds through mid week. Farther south, the southerly swell will subside tonight. $$ KRV