000 AXPZ20 KNHC 120913 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 612 UTC Mon Dec 12 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 axis extends from 08N78W to 09N84W to 07N92W. The ITCZ continues from 07N92W to 08N98W to 07N103W to 09N123W to 07N129W to 06N140W. Scattered moderate and isolated strong convection are found within 90 nm either side of a line from 07N92W to 08N104W and from 07N to 14N between 109W and 130W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Strong north winds continue this morning north of 14N with max seas of 9 ft. Residual high pressure over southern and eastern Mexico will continue to weaken, allowing winds to diminish to around 20 kt by this afternoon. Nocturnal drainage winds will pulse to around 25 kt in the Gulf of Tehuantepec during the overnight hours each night tonight through Friday night. Moderate to fresh NW winds over the offshore waters north of 20N will become gentle to moderate tonight through Thursday as seas range between 4 and 6 ft. Light to gentle north winds will prevail S of 17N through Wednesday. Between 17N and Mazatlan, gentle to moderate northwest winds will prevail through Wednesday, then become light through Friday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh offshore winds are observed east of 90W in the Papagayo region with seas less than 8 ft. A 1008 mb surface low over the Nicaragua/Costa Rica border near 11N85W will move over the Pacific west of Costa Rica today. Global models indicate some modest development of the low as it moves westward away from the offshore waters Tuesday and Wednesday. Latest global model forecasts show associated winds remaining 25 kt or less. REMAINDER OF THE AREA... A broad surface ridge over the NW forecast waters is anchored by a 1024 mb high centered near 28N130W. Gentle to moderate north- northwest flow is expected east of the high through Wednesday. Moderate to fresh NE winds are situated between the ridge and the ITCZ, or generally from 10N to 20N W of 130W. Combined seas reach 8 ft from 07N to 13N W of 136W. This area will shift west of 140W today. Low pressure and an attendant frontal boundary northwest of the area will continue weakening the ridge through Thursday. The front will briefly stall just inside the far northwest waters on Wednesday and introduce winds of 20 to 25 kt and seas to 8 ft. Then reinforcing cold air will push the front east-southeastward across the northern waters Thursday and Friday. NW swell generated behind the front will cause seas to build N of 26N and W of 120W to 8-10 feet by Friday morning. $$ cam