000 AXPZ20 KNHC 150951 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Dec 15 2017 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 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front entering the far NW Gulf of Mexico tonight will reach the Bay of Campeche Fri night. Cool and dense air will funnel through the Chivela pass into the Gulf of Tehuantepec Fri evening with winds rapidly ramping up to near gale force Fri evening and further to gale force later Fri night. The front will lose its push Saturday, which will diminish winds funneling across the Gulf of Tehuantepec. This will keep this gale force gap wind event brief as winds are expected to diminish below gale force by Sat afternoon. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ extends from 07N92W TO 07.5N113W TO beyond 10N140W. Widely scattered moderate convection is from 11.5N TO 17N between 114W AND 120W. Scattered moderate to strong convection is from 13N to 17N W OF 137W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Strong NW winds prevail over the far northern Gulf of California tonight, and will gradually shift S through the basin to near 26.5n late tonight before diminishing below 20 kt early Saturday. Winds will diminish further across the Gulf during the day Saturday, and shift S to SW ahead of an approaching cold front. The cold front will push southward across Baja California Norte into the Gulf of California this weekend with fresh to locally strong SW winds ahead of the front. Associated large swell and strong winds will spread across the Pacific waters off the coast of Baja California Norte during this time. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong winds across the Gulf of Papagayo will diminish early Fri, then strengthen again Sat night. Fresh N winds will funnel across the Gulf of Panama through late this morning before diminishing through the weekend. REMAINDER OF THE AREA... High pressure of 1029 mb centered north of the area near 36N134W extends a ridge southeast to near 20N113W. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting moderate to fresh winds north of the ITCZ to 21N and west of 118W. The tradewinds have become further enhanced to the W of 135W as a low level trough has developed just W of the area along 144W. This feature will drift N during the next 24-36 hours and maintain strong tradewinds across far W portions W of 135W. NW swell propagating through the area is supporting seas 8 ft or greater over much of the area west of 120W. Seas associated with a fresh pulse of NW swell over the NW waters are peaking near 15 ft in the area of strong trades W of 135W. Seas will slowly subside as the swell propagates southeast the next few days. A cold front will move into the far northern waters Saturday. This will usher in another set of northerly swell into the area, with seas peaking near 14 ft Saturday night near 30N122W. $$ Stripling