000 AXPZ20 KNHC 170911 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 911 UTC Sat Dec 17 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 0900 UTC. ...SPECIAL FEATURES... Gulf of California...Northwest winds to minimal gale force follow a cold front moving across Baja California Norte and into the far northern Gulf of California. There is enough of a fetch to support seas to 9 ft in this area. In addition, strong west winds funneling through low lying gaps are pushing into the Gulf of California ahead of the front. These winds diminish through this morning, but strong northwest winds will move into the central Gulf by late today before diminishing slightly into Sunday as the front stalls and dissipates over the southern Gulf. Strong Winds increase again to near gale force by late Sunday as high pressure builds north of the area. These winds will reach near gale force Monday over the far northern Gulf of California with seas building to 8 ft, before diminishing late Monday into Tuesday. Looking ahead, this pattern repeats by late Tuesday through mid week. Gulf of Tehuantepec...A cold front will move through the western Gulf of Mexico through late Sunday. Cooler, drier air behind the front will move across the isthmus of Tehuantepec into the Gulf of Tehuantepec Sunday night, with winds reaching gale force. A large plume of gale force winds will persist into early Wednesday across the Gulf of Tehuantepec, with seas reaching as high as 17 ft by late Tuesday. Winds diminish below gale force with subsiding seas through mid week as the airmass to the north modifies and shifts east. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northwest Colombia near 06N78W to 06N100W. The ITCZ continues from 06n100W and extends west to 10N110W to 09N140W. Scattered moderate convection is noted within 90 nm either side of the monsoon trough east of 80W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale warnings is in effect for the Gulf of California and Gulf of Tehuantepec. See Special Features section above for details. Fresh northerly winds are well sampled by a 0530 UTC ASCAT pass following a cold front from Baja California Norte to 26N125W. These winds will spread southward behind the front along the coast of Baja California through late today, with seas building to 5 to 8 ft. Winds and seas diminish through Sunday as the front stalls and dissipates near the southern tip of Baja California Sur. Elsewhere offshore of Mexico, and outside of the Gulf of Tehuantepec and Gulf of California, gentle to moderate breezes and 3 to 5 ft seas will persist. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong northeast winds are expected across the Gulf of Papagayo during the overnight and early morning hours through Monday, with the assistance of the nocturnal drainage flow. Seas should build 6-8 ft during the peak of each nights wind. A larger gap wind event appears to be in store for most of zone PMZ113 and southern portions of PMZ111 off El Salvador and Guatemala Monday night into Tuesday morning, as strong trade wind flow in the southwest Caribbean funnels across Central America. Marine guidance indicates fresh to strong winds across the Gulf of Fonseca and the Gulf of Papagayo extending westward to beyond 92W/93W by Tuesday morning, with seas building up to 10-11 ft W of 90W. Moderate northerly winds are expected across the Gulf of Panama at that time. REMAINDER OF THE AREA... Strong 1036 mb high pressure northwest of the area will shift eastward through the next several days, allowing northeast winds to increase across much of the area north of 10N through late Sunday. Meanwhile a persistent deep layer trough from 10N to 15N along 110W will drift west. Fresh to strong winds will cover the area from 05N to 25N west of 120W early next week between the high pressure to the north and the trough to the east. Seas will reach 13 ft in this area with the added component of longer period northwest swell. The winds diminish through mid week as the high pressure weakens and the trough dissipates. Seas of 8 to 9 ft will linger over much of the area west of a line from Baja California Norte to 05N140W. $$ CHRISTENSEN