000 AXPZ20 KNHC 110335 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Dec 11 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... Gulf of Tehuantepec Gale Warning: Strong high pressure over southern and eastern Mexico is maintaining a tight pressure gradient over the Isthmus of Tehuantepec. This gradient will support sustained winds to around 40 kt tonight, then diminish Sunday as high pressure over the western Gulf of Mexico shifts eastward. Max seas will be 14-15 ft tonight, becoming 10-12 ft Sunday then subsiding below 8 ft Monday. North winds will pulse to near 25 kt during overnight hours Monday and Tuesday. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N83W to 06N94W. The ITCZ continues from 06N96W to 06N132W to 07N140W. Scattered moderate isolated strong convection from 11N to 14N between 106W and 120W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure centered west of the area extends a ridge eastward to Baja California along 27N. Other from the Tehuantepec high wind event, light to gentle winds will prevail S of 17N through Wednesday. Fresh to locally strong NW winds north of 28N along the west coast of Baja California will continue through Sunday night, then diminish Monday as the ridge weakens in response to an area of low pressure approaching from the NW. Between 17N and Mazatlan moderate to fresh northwest winds will prevail through Tuesday night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong offshore winds east of 92W will continue to pulse mainly during the overnight hours this weekend. Max seas during this event will be 8-9 ft. An easterly wave over the western Caribbean will cross Central America early Monday. GFS model guidance indicates low pressure development along the wave axis as it moves westward away from Costa Rica on Tuesday and Wednesday. Model consensus and climatology suggest this system should remain a either a trough or possibly a low, with winds 25 kt or less. Light to gentle north to northeast winds and combined seas of 3 to 5 ft are occurring north of the monsoon trough, which is expected to meander between 08N and 10N through Wednesday. Light to moderate southwest winds are observed from 05N to 09N, with combined seas hovering between 3 and 5 ft in southwest swell. Moderate to fresh southerly flow is expected south of 05N through Wednesday. REMAINDER OF THE AREA... High pressure ridge centered near 28N129W extends southeast to 15N104W. Gentle to moderate north-northwest flow is expected northeast of the ridge axis this weekend and moderate to fresh trades will prevail south of the ridge axis, north of the ITCZ. Fresh to occasionally strong NE winds and combined seas of 8-9 ft will prevail from 07N to 15N W of 125W through Monday. Low pressure approaching the far northwestern waters will weaken the ridge, and help maintain a relatively light wind regime in this area Monday and Tuesday. A cold front will push into northwest waters Tue night, and extend from 30N135W to 27N140W Wednesday. $$ Mundell