000 AXPZ20 KNHC 290928 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 650 UTC Sat Oct 29 2016 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 0830 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning...a high pres ridge over eastern Mexico is combining with low pres over the W Caribbean to produce a tight pres gradient over the Gulf of Mexico. As a result, strong N winds will reach minimal gale force this morning. The gradient will weaken a bit thereafter, allowing for winds to remain below gale force through Thursday. Seas will reach 14 ft during the period of strongest winds early this morning. A cold front entering the Gulf of Mexico could bring renewed gales to the Gulf of Tehuantepec at the end of next week. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N85W to 08N99W to 1009 mb low pres near 10N113W to 08N120W. The ITCZ continues from 14N132W to beyond 10N140W. Scattered moderate convection is observed from 07N to 11N between 124W and 127W. Scattered moderate and isolated strong convection is present within 60 nm either side of a line from 17N132W to 12N138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See the special features section for details on a persistent Gulf of Tehuantepec high wind event. Gentle to moderate NW winds prevail across the waters offshore of the Baja California peninsula. Winds will remain relatively light this weekend as an approaching cold front weakens the ridge to the NW. 4 to 5 ft seas will build to 6 to 9 ft in NW swell Sunday as a cold front crosses the northern waters. The front will slowly weaken W of Baja Norte early next week. Associated swells will decay by Tuesday. An elongated NW to SE trough lingers over the northern Gulf of California. An area of low pres is developing in the trough N of 30N. Winds on the SE side of the low will become moderate to fresh at times through Monday. 1 to 2 ft seas will build to between 4 and 7 ft as the winds increase, with 2 to 4 ft seas expected over the southern half of the Gulf of California through early next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle W to NW winds will prevail N of the monsoon trough except for moderate offshore winds in nocturnal drainage flow Saturday night through Tuesday. Moderate SW winds S of the monsoon trough will increase this weekend through early next week. 4 to 6 ft seas will subside to 3 to 5 ft this weekend, then build early next week to 5 to 7 ft. REMAINDER OF THE AREA... The remnant low of Seymour is located near 23N121W. Latest satellite-derived wind data indicate winds in the vicinity of the low have diminished to between 10 and 15 kt. Altimetry indicates associated seas of 7-8 ft. Winds and seas near the low will continue to diminish. The remnant low is expected to dissipate by Monday morning. A cold front extending from 30N132W to 27N140W will quickly move across the northern waters and usher in a reinforcing set of NW swell. Seas will build to 12 to 16 ft along 30N by early Sunday, then subside Sunday night through Monday night. Model guidance shows another front with an even more impressive set of NW swell arriving late Tuesday night. Otherwise, moderate to fresh trades S of 20N and W of 125W will increase slightly Sunday through early next week as high pres builds in behind the next front and a broad trough of low pres moves W along the convergence zone toward 140W. $$ cam