000 AXPZ20 KNHC 150336 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 336 UTC Tue Nov 15 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... The pressure gradient between high pressure over eastern Mexico and lower pressure within the monsoon trough over the eastern north Pacific continues to support winds of near gale force to minimal gale force over the Gulf of Tehuantepec. A reinforcing front moving across the Gulf of Mexico will help winds to maintain above gale force over the Gulf of Tehuantepec through midweek. Winds over the southwest Gulf of Mexico will veer as the area of high pressure shifts eastward into the southeast United States toward the end of the week. This will decrease winds flowing through the Chivela pass and bring an end to this extended period of gale force winds over the Gulf of Tehuantepec by Thursday. Looking ahead to Friday night, another cold front is forecast to move across the Gulf of Mexico which may lead to yet another gale force gap wind event over the Gulf of Tehuantepec next Friday night into the weekend. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 09N100W to 10N106W. It resumes from 14N112W to low pressure near 12N128W 1009 mb to 08N140W. Scattered moderate convection within 30 nm in the northeast quadrant of the low pressure centered near 12N128W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see special features section above for more details on the ongoing Gulf of Tehuantepec gale force gap wind event. Recently downgraded Post-Tropical Cyclone Tina is centered near 18.9N 109.8W at 15/0300 UTC, moving west or 270 degrees at 6 kt. Maximum sustained wind speed is 25 kt with gusts to 35 kt. No significant convection is noted. This system will continue to spin down as it shifts westward over the next day or so, and is expected to dissipate by late Tuesday. Outside the influence of Post-Tropical Cyclone Tina and the Gulf of Tehuantepec gap wind event, northwesterly swell continues to propagate through the open Pacific waters off the western coast of Baja California. Seas over this area are in the 8-10 ft range. This swell will subside and seas will fall below 8 ft by Tuesday. High pressure building north of the area will tighten the pressure gradient off the coast of California and Baja California Norte by midweek. This will strengthen winds to 25 kt off the coast of Baja California Norte Wednesday night, with winds reaching gale force off the coast of California. The gale force winds will help generate another northwesterly swell which will propagate into the waters off the coast of Baja California Norte by early Thursday. Seas will peak near 14 ft early Thursday before starting to subside. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Pulsing winds of 15 to 20 kt are expected over the Gulf of Papagayo during the next several days, with seas building to 5-6 ft downstream of the Gulf of Papagayo. Elsewhere, light to gentle winds will prevail over the waters north of 10N, with gentle to moderate mainly southwest winds south of 10N. A surge in southwest monsoon flow aided by developing low pressure over the southwest Caribbean will freshen winds over the southern waters midweek. REMAINDER OF THE AREA... A subsiding northwest swell continues to propagate through the region. Seas associated to this swell are forecast to subside below 8 ft by midweek. A fresh set of northwesterly swell will move into the northwestern waters Tuesday with seas peaking near 11 ft late Tuesday into Wednesday over the far northwest waters. The pressure gradient will tighten between lower pressure in the vicinity of the ITCZ and developing high pressure north of the area. This will bring an increase in the trade wind flow over the far western waters north of the ITCZ by Tuesday. A 1009 mb low pressure centered along the monsoon trough near 12N128W will move west into Tuesday along the monsoon trough, then dissipate Tuesday night. $$ CHRISTENSEN