000 AXPZ20 KNHC 061640 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1435 UTC Tue Dec 6 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 1200 UTC surface analysis and satellite imagery through 1415 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N75W to 08N80W to 11N93W. The intertropical convergence zone axis extends from 11N103W to 08N120W to 09N140W. Scattered moderate and isolated strong convection is from 05N to 08N between 78W and 81W. Similar convection is within 180 nm north of a line from 14N103W to 06N126W to 06N134W, and also from 07N to 08N between 136W and 139W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: A trough is expected to develop from weak low pressure over northwest Mexico near 32N114W to the south across the northern gulf. Moderate to locally fresh southerly flow is expected southeast of the trough to 29N, with the strongest winds near Isla San Luis. The next cold front is expected to pass across the northern gulf waters on Wednesday. Light and variable winds are forecast across the gulf waters south of 29N through Wednesday, then becoming northwesterly behind the front. Fresh northwest flow will arrive behind the front on Thursday, except locally strong across the central and southern gulf waters. A ridge will meander across the area from roughly 23N116W to 16N103W through mid week. Gentle to moderate anticyclonic flow is forecast around the ridge as long period northwest swell continues to subside, with the highest seas of 5 to 8 ft persisting 120 nm seaward to the north of 29N through Wednesday. A low level trough extends from 16N102W to 14N105W with clusters of moderate to locally strong convection occasionally flaring across zone PMZ025. Gulf of Tehuantepec: Gentle to moderate southerly flow will shift to northerly with nocturnal drainage flow late tonight, and again late Wednesday night. A strong cold front will move through the southwest Gulf of Mexico north of the area by the end of the week, with high pressure surging down across eastern Mexico. Northerly winds in the Gulf of Tehuantepec will rapidly increase to gale force Thursday night, continuing through Saturday afternoon. Seas will build to near 18 ft downstream of the gulf. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh nocturnal offshore flow will resume Wednesday night and Thursday night, increasing to strong Friday night and Saturday night. Mostly light to gentle northerly winds, and combined seas of 4 to 6 ft, are occurring elsewhere north of 09N/10N, while light to moderate southwest flow is observed to the south of 09N/10N. Combined seas of 3 to 5 ft, in mixing long-period northwest and southwest swell, are expected this week. REMAINDER OF THE AREA... A surface ridge extends southeast from 30N131W to 17N112W. The parent surface high will shift into the north central waters near 29N123W by late Wednesday night. This high will strengthen some and block the eastward advance of a cold front, causing it to stall from 32N137W to 31N140W on Thursday. Moderate to locally fresh northwest to north flow is expected to the northeast of the ridge this week, except fresh to locally strong breeze forecast along 32N at 120W. Moderate to locally fresh northeast trades currently south of the ridge are expected to weaken from the north today, then increase to moderate to locally fresh again on Wednesday through Thursday, with the fresh winds expected just north of the ITCZ. Combined seas of 6 to 8 ft in mixing northeast winds waves and long period northwest swell currently north of the ITCZ and west of 109W, are expected to gradually subside to less than 8 ft by late tonight. $$ LEWITSKY