000 AXPZ20 KNHC 271619 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Fri Jan 27 2017 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 1500 UTC. ...SPECIAL FEATURES... Eastern Pacific Gale Warning: A broad and very complex area of low pressure prevails across SW portions of the discussion area, and is most easily described as trough extending from 11.5N128W to 13N142W. The pressure gradient between this area of lower pressure and the subtropical ridge to the north of the area is supporting a broad area of near gale to gale force winds within 300 nm north of the trough, surrounded by a large area of strong to near gale force trade winds from north of the trough to 26N west of 121W. Seas are 12 to 20 ft in the area of strongest winds as longer period northwest swell is propagating through the region of large wind driven easterly waves. The gale force winds will diminish through Saturday as the low pressure area gradually weakens and shifts west of 140W. Gulf of California and Baja California peninsula Gale Warnings: 1044 mb high pressure is noted over the Great Basin, supporting strong to near gale force winds along the length of the Gulf of California this morning. Some of this wind flow is crossing over relatively lower mountain peaks along the Baja California peninsula, with strong northeast winds pushing into Sebastian Vizcaino Bay and adjacent waters off Baja California. These winds will increase to gale force this afternoon both across the Pacific waters of Baja California Norte, and throughout the majority of the Gulf of California and continue through early Saturday as high pressure builds to the north, then will diminish through Sunday. Unusually high seas will be generated inside the Gulf of California, and increase to 8 to 13 ft, with the potential for isolated areas to 15 ft, while seas of 8 to 13 ft develop off the Baja California peninsula in mixed long period NW swell. Marine interests across the Gulf of California should prepare for periods of gale force winds and large wind driven north winds over the next 24-36 hours. See the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFEP2/FZPN03 KNHC for additional details on these warnings. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ extends from near 04.5N85W to 02N100W to 06N120W to broad and complex low pressure centered 15N135W. Scattered to locally numerous moderate to strong convection is noted from 08.5N to 18N between 131.5W and 140W, and from 13N to 21N between 124W and 131W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See special features section above for gale conditions along the Baja Peninsula and across the Gulf of California. Long period nw swell dominated most of the area waters west of 120W this morning, with seas running 8 to 14 ft there per overnight altimeter data. These seas will be reinforced by another pulse of NW swell with seas of 11 to 13 ft propagating southeast across the waters offshore to the north of 28N through Fri night. Mixing southwest and northwest swell resulting in seas of 4 to 7 ft are expected between 95W and 110W into Fri, then build from the north again on Fri night into Sat. Gulf of Tehuantepec: strong to near gale force northerly winds overnight built seas to 10 ft at sunrise. These north winds have begun to diminish this morning and will fall to a fresh breeze this afternoon, then increase to a strong breeze again briefly late Friday night. A stronger gap wind event is forecast beginning on Saturday evening with gale conditions Sat night through sunrise on Tuesday. The strongest winds of 30 to 40 kt area expected on Monday evening with seas building to 18 ft near 14N96W. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong winds are forecast briefly around sunrise, then diminishing through midday. Stronger gap events are forecast tonight through Tuesday nights, with seas building to about 10 ft downstream of the Gulf waters near 10N88W on Tuesday. Gulf of Panama: Fresh n nocturnal winds expected each night through the upcoming weekend.. Light to gentle winds, and combined seas of 3 to 5 ft, are occurring elsewhere until swells from the gap events develop over the upcoming weekend. REMAINDER OF THE AREA... See special features section above for a gale warning near 15N135W. Otherwise, large northwest swell with combined seas to 12 ft currently across the discussion waters west of 110W will gradually subside. Strong southerly winds and large seas will spread e over the waters n of 22N w of 138W beginning on Sunday, ahead of a cold front reaching 32N140W late Tuesday. $$ Stripling