000 AXPZ20 KNHC 140942 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 706 UTC Wed Dec 14 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N77W to 10N91W to 1010 MB low pressure near 09N96W to 07N102W. The ITCZ continues from 07N102W to 08N111W to 07N127W to 09N132W...then resumes near 12N136W to beyond 11N140W. Scattered moderate and isolated strong convection is observed from 05N to 09N between 77W and 83W and from 09N to 11N between 119W and 127W. Scattered moderate convection is noted from 08N to 11N between 93W and 98W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Winds in the vicinity of the Gulf of Tehuantepec remain light and variable. A modest high pressure ridge across the SW Gulf of Mexico will maintain enough pressure gradient to produce fresh to strong N to NE nocturnal drainage winds later this morning over the Gulf of Tehuantepec. A new cold front will cross the northern Gulf of Mexico today and reinforce the high pressure ridge over the Gulf. This will boost the drainage winds into the Gulf of Tehuantepec tonight through the remainder of the work week. Minimal gale force winds are expected Thursday evening through Friday morning as a result. A stronger cold front could produce a more robust gale wind event beginning on Monday. Moderate northwest winds over the offshore waters north of 20N will become gentle to moderate by Thursday evening with 3-5 ft seas prevailing. A cold front will move into the area from the west, and extend from near San Diego, CA to near 29N121W around midday on Friday. The front will then sweep southeastward across the Baja Peninsula and NW Mexico to pass south of Cabo San Lucas by Saturday evening. Model guidance shows strong southwest to west winds ahead of the front and strong to near-gale force west to northwest winds behind the front over the northern Gulf of California on Friday night. Fresh to strong NW winds will affect the offshore zones N of 25N on Saturday and Saturday night, with seas building as high as 10 ft near 30N. Gentle north to northwest winds will prevail south of Mazatlan today. The winds will become light Thursday through Saturday, then become light to moderate on Sunday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak 1010 mb surface low currently centered south of Tehuantepec near 09N96W will continue moving westward away from the forecast area during the next several days. Global models call for the low to gradually weaken into a trough by Saturday. Fresh to strong nocturnal drainage winds will affect the Gulf of Papagayo E of 88W tonight through Saturday night. A larger event appears to be in store for most of zone PMZ113 on Tuesday morning. REMAINDER OF THE AREA... Broad high pressure of 1021 mb centered near 31N123W lingers over the northern waters. Gentle to moderate NNW winds are expected east of the high today. A trough of low pressure is moving westward across the west portions of the trade wind belt. The trough is currently analyzed from 11N136W to 14N135W to 19N133W. The pressure gradient between the high and weak low pressure developing in the trough is expected to generate winds of 20 to 25 kt and seas to 8 ft in the E quadrant of the low within 150 nm. The trough and low are expected to gradually weaken as they translate northwestward during the 24 to 36 hours, allowing associated winds and seas to subside by Friday afternoon. The remnants of the trough will gradually lift northward Thu and Fri, ahead of the cold frontal boundary due to enter the far NW waters this afternoon. South to southwest winds between 20 and 25 kt and 8-10 ft seas will precede the front today. Reinforcing cold air will reinvigorate the front and push it east-southeastward across the northern waters Thursday and Friday. NW swell generated behind the front will cause seas north of 25N and west of 120W to build to 8-10 feet by Friday. Seas east of 130W will briefly subside to around 8 ft on Saturday before a round of reinforcing N swell arrives on Sunday. High pressure building N of the area will cause a large area of fresh to strong trades to develop N of the ITCZ from 07N to 25N W of 125W by Tuesday morning. Seas in this area will be in the 8 to 11 foot range. $$ cam